Oh GACK! src-clean doesn't quite work that easily since cleandist rebuilds the

[unix-history] / lib / libc / db / doc / hash.ps

%!PS-Adobe-1.0
%%Creator: utopia:margo (& Seltzer,608-13E,8072,)
%%Title: stdin (ditroff)
%%CreationDate: Tue Dec 11 15:06:45 1990
%%EndComments
%	@(#)psdit.pro	1.3 4/15/88
% lib/psdit.pro -- prolog for psdit (ditroff) files
% Copyright (c) 1984, 1985 Adobe Systems Incorporated. All Rights Reserved.
% last edit: shore Sat Nov 23 20:28:03 1985
% RCSID: $Header: psdit.pro,v 2.1 85/11/24 12:19:43 shore Rel $

% Changed by Edward Wang (edward@ucbarpa.berkeley.edu) to handle graphics,
% 17 Feb, 87.

/$DITroff 140 dict def $DITroff begin
/fontnum 1 def /fontsize 10 def /fontheight 10 def /fontslant 0 def
/xi{0 72 11 mul translate 72 resolution div dup neg scale 0 0 moveto
 /fontnum 1 def /fontsize 10 def /fontheight 10 def /fontslant 0 def F
 /pagesave save def}def
/PB{save /psv exch def currentpoint translate 
 resolution 72 div dup neg scale 0 0 moveto}def
/PE{psv restore}def
/arctoobig 90 def /arctoosmall .05 def
/m1 matrix def /m2 matrix def /m3 matrix def /oldmat matrix def
/tan{dup sin exch cos div}def
/point{resolution 72 div mul}def
/dround	{transform round exch round exch itransform}def
/xT{/devname exch def}def
/xr{/mh exch def /my exch def /resolution exch def}def
/xp{}def
/xs{docsave restore end}def
/xt{}def
/xf{/fontname exch def /slotno exch def fontnames slotno get fontname eq not
 {fonts slotno fontname findfont put fontnames slotno fontname put}if}def
/xH{/fontheight exch def F}def
/xS{/fontslant exch def F}def
/s{/fontsize exch def /fontheight fontsize def F}def
/f{/fontnum exch def F}def
/F{fontheight 0 le{/fontheight fontsize def}if
 fonts fontnum get fontsize point 0 0 fontheight point neg 0 0 m1 astore
 fontslant 0 ne{1 0 fontslant tan 1 0 0 m2 astore m3 concatmatrix}if
 makefont setfont .04 fontsize point mul 0 dround pop setlinewidth}def
/X{exch currentpoint exch pop moveto show}def
/N{3 1 roll moveto show}def
/Y{exch currentpoint pop exch moveto show}def
/S{show}def
/ditpush{}def/ditpop{}def
/AX{3 -1 roll currentpoint exch pop moveto 0 exch ashow}def
/AN{4 2 roll moveto 0 exch ashow}def
/AY{3 -1 roll currentpoint pop exch moveto 0 exch ashow}def
/AS{0 exch ashow}def
/MX{currentpoint exch pop moveto}def
/MY{currentpoint pop exch moveto}def
/MXY{moveto}def
/cb{pop}def	% action on unknown char -- nothing for now
/n{}def/w{}def
/p{pop showpage pagesave restore /pagesave save def}def
/Dt{/Dlinewidth exch def}def 1 Dt
/Ds{/Ddash exch def}def -1 Ds
/Di{/Dstipple exch def}def 1 Di
/Dsetlinewidth{2 Dlinewidth mul setlinewidth}def
/Dsetdash{Ddash 4 eq{[8 12]}{Ddash 16 eq{[32 36]}
 {Ddash 20 eq{[32 12 8 12]}{[]}ifelse}ifelse}ifelse 0 setdash}def
/Dstroke{gsave Dsetlinewidth Dsetdash 1 setlinecap stroke grestore
 currentpoint newpath moveto}def
/Dl{rlineto Dstroke}def
/arcellipse{/diamv exch def /diamh exch def oldmat currentmatrix pop
 currentpoint translate 1 diamv diamh div scale /rad diamh 2 div def
 currentpoint exch rad add exch rad -180 180 arc oldmat setmatrix}def
/Dc{dup arcellipse Dstroke}def
/De{arcellipse Dstroke}def
/Da{/endv exch def /endh exch def /centerv exch def /centerh exch def
 /cradius centerv centerv mul centerh centerh mul add sqrt def
 /eradius endv endv mul endh endh mul add sqrt def
 /endang endv endh atan def
 /startang centerv neg centerh neg atan def
 /sweep startang endang sub dup 0 lt{360 add}if def
 sweep arctoobig gt
 {/midang startang sweep 2 div sub def /midrad cradius eradius add 2 div def
  /midh midang cos midrad mul def /midv midang sin midrad mul def
  midh neg midv neg endh endv centerh centerv midh midv Da
  Da}
 {sweep arctoosmall ge
  {/controldelt 1 sweep 2 div cos sub 3 sweep 2 div sin mul div 4 mul def
   centerv neg controldelt mul centerh controldelt mul
   endv neg controldelt mul centerh add endh add
   endh controldelt mul centerv add endv add
   centerh endh add centerv endv add rcurveto Dstroke}
  {centerh endh add centerv endv add rlineto Dstroke}
  ifelse}
 ifelse}def
/Dpatterns[
[%cf[widthbits]
[8<0000000000000010>]
[8<0411040040114000>]
[8<0204081020408001>]
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[8<0000000000000010>]
[8<0411040040114000>]
[8<0204081020408001>]
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[8<6699996666999966>]
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[8<0042660000246600>]
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[8<0804020180402010>]
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[8<6699996666999966>]
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[8<00001c3e363e1c00>]
[8<0000000000000000>]
[32<00000040000000c00000004000000040000000e0000000000000000000000000>]
[32<00000000000060000000900000002000000040000000f0000000000000000000>]
[32<000000000000000000e0000000100000006000000010000000e0000000000000>]
[32<00000000000000002000000060000000a0000000f00000002000000000000000>]
[32<0000000e0000000000000000000000000000000f000000080000000e00000001>]
[32<0000090000000600000000000000000000000000000007000000080000000e00>]
[32<00010000000200000004000000040000000000000000000000000000000f0000>]
[32<0900000006000000090000000600000000000000000000000000000006000000>]]
[%ug
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[8<9f0f0f9ff9f0f0f8>]
[8<9f0f0f9ff9f0f0f9>]
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[8<9f8f0f9ff9f8f0f9>]
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[8<bf8f1f9ffbf8f1f9>]
[8<bf8f1fdffbf8f1f9>]
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[8<ff9f1ffffff9f1ff>]
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[8<ff9f9ffffff9f9ff>]
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[8<ffbfdffffffbfdff>]
[8<ffffdffffffbfdff>]
[8<ffffdffffffffdff>]
[8<fffffffffffffdff>]
[8<ffffffffffffffff>]]
[%mg
[8<8000000000000000>]
[8<0822080080228000>]
[8<0204081020408001>]
[8<40e0400000000000>]
[8<66999966>]
[8<8001000010080000>]
[8<81c36666c3810000>]
[8<f0e0c08000000000>]
[16<07c00f801f003e007c00f800f001e003c007800f001f003e007c00f801f003e0>]
[16<1f000f8007c003e001f000f8007c003e001f800fc007e003f001f8007c003e00>]
[8<c3c300000000c3c3>]
[16<0040008001000200040008001000200040008000000100020004000800100020>]
[16<0040002000100008000400020001800040002000100008000400020001000080>]
[16<1fc03fe07df0f8f8f07de03fc01f800fc01fe03ff07df8f87df03fe01fc00f80>]
[8<80>]
[8<8040201000000000>]
[8<84cc000048cc0000>]
[8<9900009900000000>]
[8<08040201804020100800020180002010>]
[8<2418814242811824>]
[8<66999966>]
[8<8000000008000000>]
[8<70f8d8f870000000>]
[8<0814224180402010>]
[8<aa00440a11a04400>]
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[8<88000000>]
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[8<00>]]]def
/Dfill{
 transform /maxy exch def /maxx exch def
 transform /miny exch def /minx exch def
 minx maxx gt{/minx maxx /maxx minx def def}if
 miny maxy gt{/miny maxy /maxy miny def def}if
 Dpatterns Dstipple 1 sub get exch 1 sub get
 aload pop /stip exch def /stipw exch def /stiph 128 def
 /imatrix[stipw 0 0 stiph 0 0]def
 /tmatrix[stipw 0 0 stiph 0 0]def
 /minx minx cvi stiph idiv stiph mul def
 /miny miny cvi stipw idiv stipw mul def
 gsave eoclip 0 setgray
 miny stiph maxy{
  tmatrix exch 5 exch put
  minx stipw maxx{
   tmatrix exch 4 exch put tmatrix setmatrix
   stipw stiph true imatrix {stip} imagemask
  }for
 }for
 grestore
}def
/Dp{Dfill Dstroke}def
/DP{Dfill currentpoint newpath moveto}def
end

/ditstart{$DITroff begin
 /nfonts 60 def			% NFONTS makedev/ditroff dependent!
 /fonts[nfonts{0}repeat]def
 /fontnames[nfonts{()}repeat]def
/docsave save def
}def

% character outcalls
/oc{
 /pswid exch def /cc exch def /name exch def
 /ditwid pswid fontsize mul resolution mul 72000 div def
 /ditsiz fontsize resolution mul 72 div def
 ocprocs name known{ocprocs name get exec}{name cb}ifelse
}def
/fractm [.65 0 0 .6 0 0] def
/fraction{
 /fden exch def /fnum exch def gsave /cf currentfont def
 cf fractm makefont setfont 0 .3 dm 2 copy neg rmoveto
 fnum show rmoveto currentfont cf setfont(\244)show setfont fden show 
 grestore ditwid 0 rmoveto
}def
/oce{grestore ditwid 0 rmoveto}def
/dm{ditsiz mul}def
/ocprocs 50 dict def ocprocs begin
(14){(1)(4)fraction}def
(12){(1)(2)fraction}def
(34){(3)(4)fraction}def
(13){(1)(3)fraction}def
(23){(2)(3)fraction}def
(18){(1)(8)fraction}def
(38){(3)(8)fraction}def
(58){(5)(8)fraction}def
(78){(7)(8)fraction}def
(sr){gsave 0 .06 dm rmoveto(\326)show oce}def
(is){gsave 0 .15 dm rmoveto(\362)show oce}def
(->){gsave 0 .02 dm rmoveto(\256)show oce}def
(<-){gsave 0 .02 dm rmoveto(\254)show oce}def
(==){gsave 0 .05 dm rmoveto(\272)show oce}def
(uc){gsave currentpoint 400 .009 dm mul add translate
     8 -8 scale ucseal oce}def
end

% an attempt at a PostScript FONT to implement ditroff special chars
% this will enable us to 
%	cache the little buggers
%	generate faster, more compact PS out of psdit
%	confuse everyone (including myself)!
50 dict dup begin
/FontType 3 def
/FontName /DIThacks def
/FontMatrix [.001 0 0 .001 0 0] def
/FontBBox [-260 -260 900 900] def% a lie but ...
/Encoding 256 array def
0 1 255{Encoding exch /.notdef put}for
Encoding
 dup 8#040/space put %space
 dup 8#110/rc put %right ceil
 dup 8#111/lt put %left  top curl
 dup 8#112/bv put %bold vert
 dup 8#113/lk put %left  mid curl
 dup 8#114/lb put %left  bot curl
 dup 8#115/rt put %right top curl
 dup 8#116/rk put %right mid curl
 dup 8#117/rb put %right bot curl
 dup 8#120/rf put %right floor
 dup 8#121/lf put %left  floor
 dup 8#122/lc put %left  ceil
 dup 8#140/sq put %square
 dup 8#141/bx put %box
 dup 8#142/ci put %circle
 dup 8#143/br put %box rule
 dup 8#144/rn put %root extender
 dup 8#145/vr put %vertical rule
 dup 8#146/ob put %outline bullet
 dup 8#147/bu put %bullet
 dup 8#150/ru put %rule
 dup 8#151/ul put %underline
 pop
/DITfd 100 dict def
/BuildChar{0 begin
 /cc exch def /fd exch def
 /charname fd /Encoding get cc get def
 /charwid fd /Metrics get charname get def
 /charproc fd /CharProcs get charname get def
 charwid 0 fd /FontBBox get aload pop setcachedevice
 2 setlinejoin 40 setlinewidth
 newpath 0 0 moveto gsave charproc grestore
 end}def
/BuildChar load 0 DITfd put
/CharProcs 50 dict def
CharProcs begin
/space{}def
/.notdef{}def
/ru{500 0 rls}def
/rn{0 840 moveto 500 0 rls}def
/vr{0 800 moveto 0 -770 rls}def
/bv{0 800 moveto 0 -1000 rls}def
/br{0 840 moveto 0 -1000 rls}def
/ul{0 -140 moveto 500 0 rls}def
/ob{200 250 rmoveto currentpoint newpath 200 0 360 arc closepath stroke}def
/bu{200 250 rmoveto currentpoint newpath 200 0 360 arc closepath fill}def
/sq{80 0 rmoveto currentpoint dround newpath moveto
    640 0 rlineto 0 640 rlineto -640 0 rlineto closepath stroke}def
/bx{80 0 rmoveto currentpoint dround newpath moveto
    640 0 rlineto 0 640 rlineto -640 0 rlineto closepath fill}def
/ci{500 360 rmoveto currentpoint newpath 333 0 360 arc
    50 setlinewidth stroke}def

/lt{0 -200 moveto 0 550 rlineto currx 800 2cx s4 add exch s4 a4p stroke}def
/lb{0 800 moveto 0 -550 rlineto currx -200 2cx s4 add exch s4 a4p stroke}def
/rt{0 -200 moveto 0 550 rlineto currx 800 2cx s4 sub exch s4 a4p stroke}def
/rb{0 800 moveto 0 -500 rlineto currx -200 2cx s4 sub exch s4 a4p stroke}def
/lk{0 800 moveto 0 300 -300 300 s4 arcto pop pop 1000 sub
    0 300 4 2 roll s4 a4p 0 -200 lineto stroke}def
/rk{0 800 moveto 0 300 s2 300 s4 arcto pop pop 1000 sub
    0 300 4 2 roll s4 a4p 0 -200 lineto stroke}def
/lf{0 800 moveto 0 -1000 rlineto s4 0 rls}def
/rf{0 800 moveto 0 -1000 rlineto s4 neg 0 rls}def
/lc{0 -200 moveto 0 1000 rlineto s4 0 rls}def
/rc{0 -200 moveto 0 1000 rlineto s4 neg 0 rls}def
end

/Metrics 50 dict def Metrics begin
/.notdef 0 def
/space 500 def
/ru 500 def
/br 0 def
/lt 416 def
/lb 416 def
/rt 416 def
/rb 416 def
/lk 416 def
/rk 416 def
/rc 416 def
/lc 416 def
/rf 416 def
/lf 416 def
/bv 416 def
/ob 350 def
/bu 350 def
/ci 750 def
/bx 750 def
/sq 750 def
/rn 500 def
/ul 500 def
/vr 0 def
end

DITfd begin
/s2 500 def /s4 250 def /s3 333 def
/a4p{arcto pop pop pop pop}def
/2cx{2 copy exch}def
/rls{rlineto stroke}def
/currx{currentpoint pop}def
/dround{transform round exch round exch itransform} def
end
end
/DIThacks exch definefont pop
ditstart
(psc)xT
576 1 1 xr
1(Times-Roman)xf 1 f
2(Times-Italic)xf 2 f
3(Times-Bold)xf 3 f
4(Times-BoldItalic)xf 4 f
5(Helvetica)xf 5 f
6(Helvetica-Bold)xf 6 f
7(Courier)xf 7 f
8(Courier-Bold)xf 8 f
9(Symbol)xf 9 f
10(DIThacks)xf 10 f
10 s
1 f
xi
%%EndProlog

%%Page: 1 1
10 s 10 xH 0 xS 1 f
3 f
22 s
1249 626(A)N
1420(N)X
1547(ew)X
1796(H)X
1933(ashing)X
2467(P)X
2574(ackage)X
3136(for)X
3405(U)X
3532(N)X
3659(IX)X
2 f
20 s
3855 562(1)N
1 f
12 s
1607 779(Margo)N
1887(Seltzer)X
9 f
2179(-)X
1 f
2256(University)X
2686(of)X
2790(California,)X
3229(Berkeley)X
2015 875(Ozan)N
2242(Yigit)X
9 f
2464(-)X
1 f
2541(York)X
2762(University)X
3 f
2331 1086(ABSTRACT)N
1 f
10 s
1152 1222(UNIX)N
1385(support)X
1657(of)X
1756(disk)X
1921(oriented)X
2216(hashing)X
2497(was)X
2654(originally)X
2997(provided)X
3314(by)X
2 f
3426(dbm)X
1 f
3595([ATT79])X
3916(and)X
1152 1310(subsequently)N
1595(improved)X
1927(upon)X
2112(in)X
2 f
2199(ndbm)X
1 f
2402([BSD86].)X
2735(In)X
2826(AT&T)X
3068(System)X
3327(V,)X
3429(in-memory)X
3809(hashed)X
1152 1398(storage)N
1420(and)X
1572(access)X
1814(support)X
2090(was)X
2251(added)X
2479(in)X
2577(the)X
2 f
2711(hsearch)X
1 f
3000(library)X
3249(routines)X
3542([ATT85].)X
3907(The)X
1152 1486(result)N
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1457(a)X
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1789(with)X
1968(two)X
2125(incompatible)X
2580(hashing)X
2865(schemes,)X
3193(each)X
3377(with)X
3555(its)X
3666(own)X
3840(set)X
3965(of)X
1152 1574(shortcomings.)N
1152 1688(This)N
1316(paper)X
1517(presents)X
1802(the)X
1922(design)X
2152(and)X
2289(performance)X
2717(characteristics)X
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3286(a)X
3343(new)X
3498(hashing)X
3768(package)X
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1539(superset)X
1822(of)X
1909(the)X
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2456(provided)X
2761(by)X
2 f
2861(dbm)X
1 f
3019(and)X
2 f
3155(hsearch)X
1 f
3409(.)X
3469(The)X
3614(new)X
3768(package)X
1152 1864(uses)N
1322(linear)X
1537(hashing)X
1818(to)X
1912(provide)X
2189(ef\256cient)X
2484(support)X
2755(of)X
2853(both)X
3026(memory)X
3324(based)X
3538(and)X
3685(disk)X
3849(based)X
1152 1952(hash)N
1319(tables)X
1526(with)X
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2115(superior)X
2398(to)X
2480(both)X
2 f
2642(dbm)X
1 f
2800(and)X
2 f
2936(hsearch)X
1 f
3210(under)X
3413(most)X
3588(conditions.)X
3 f
1380 2128(Introduction)N
1 f
892 2260(Current)N
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1768(offer)X
1984(two)X
2163(forms)X
2409(of)X
720 2348(hashed)N
973(data)X
1137(access.)X
2 f
1413(Dbm)X
1 f
1599(and)X
1745(its)X
1850(derivatives)X
2231(provide)X
720 2436(keyed)N
939(access)X
1171(to)X
1259(disk)X
1418(resident)X
1698(data)X
1858(while)X
2 f
2062(hsearch)X
1 f
2342(pro-)X
720 2524(vides)N
929(access)X
1175(for)X
1309(memory)X
1616(resident)X
1910(data.)X
2124(These)X
2356(two)X
720 2612(access)N
979(methods)X
1302(are)X
1453(incompatible)X
1923(in)X
2037(that)X
2209(memory)X
720 2700(resident)N
1011(hash)X
1195(tables)X
1419(may)X
1593(not)X
1731(be)X
1843(stored)X
2075(on)X
2191(disk)X
2360(and)X
720 2788(disk)N
884(resident)X
1169(tables)X
1387(cannot)X
1632(be)X
1739(read)X
1909(into)X
2063(memory)X
2360(and)X
720 2876(accessed)N
1022(using)X
1215(the)X
1333(in-memory)X
1709(routines.)X
2 f
892 2990(Dbm)N
1 f
1091(has)X
1241(several)X
1512(shortcomings.)X
2026(Since)X
2247(data)X
2423(is)X
720 3078(assumed)N
1032(to)X
1130(be)X
1242(disk)X
1411(resident,)X
1721(each)X
1905(access)X
2146(requires)X
2440(a)X
720 3166(system)N
963(call,)X
1120(and)X
1257(almost)X
1491(certainly,)X
1813(a)X
1869(disk)X
2022(operation.)X
2365(For)X
720 3254(extremely)N
1072(large)X
1264(databases,)X
1623(where)X
1851(caching)X
2131(is)X
2214(unlikely)X
720 3342(to)N
810(be)X
914(effective,)X
1244(this)X
1386(is)X
1466(acceptable,)X
1853(however,)X
2177(when)X
2378(the)X
720 3430(database)N
1022(is)X
1100(small)X
1298(\(i.e.)X
1447(the)X
1569(password)X
1896(\256le\),)X
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720 3518(improvements)N
1204(can)X
1342(be)X
1443(obtained)X
1744(through)X
2018(caching)X
2293(pages)X
720 3606(of)N
818(the)X
947(database)X
1255(in)X
1348(memory.)X
1685(In)X
1782(addition,)X
2 f
2094(dbm)X
1 f
2262(cannot)X
720 3694(store)N
902(data)X
1062(items)X
1261(whose)X
1492(total)X
1660(key)X
1802(and)X
1943(data)X
2102(size)X
2252(exceed)X
720 3782(the)N
850(page)X
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1191(of)X
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1420(hash)X
1599(table.)X
1827(Similarly,)X
2176(if)X
2257(two)X
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720 3870(more)N
907(keys)X
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1357(the)X
1477(same)X
1664(hash)X
1833(value)X
2029(and)X
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876(exceeds)X
1162(the)X
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1474(size,)X
1650(the)X
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1966(cannot)X
2210(store)X
2396(all)X
720 4046(the)N
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1142(keys.)X
892 4160(The)N
1050(in-memory)X
2 f
1439(hsearch)X
1 f
1725(routines)X
2015(have)X
2199(different)X
720 4248(shortcomings.)N
1219(First,)X
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1539(notion)X
1771(of)X
1865(a)X
1928(single)X
2146(hash)X
2320(table)X
720 4336(is)N
807(embedded)X
1171(in)X
1266(the)X
1397(interface,)X
1732(preventing)X
2108(an)X
2217(applica-)X
720 4424(tion)N
902(from)X
1116(accessing)X
1482(multiple)X
1806(tables)X
2050(concurrently.)X
720 4512(Secondly,)N
1063(the)X
1186(routine)X
1438(to)X
1525(create)X
1743(a)X
1804(hash)X
1976(table)X
2157(requires)X
2440(a)X
720 4600(parameter)N
1066(which)X
1286(declares)X
1573(the)X
1694(size)X
1842(of)X
1932(the)X
2053(hash)X
2223(table.)X
2422(If)X
720 4688(this)N
856(size)X
1001(is)X
1074(set)X
1183(too)X
1305(low,)X
1465(performance)X
1892(degradation)X
2291(or)X
2378(the)X
720 4776(inability)N
1008(to)X
1092(add)X
1230(items)X
1425(to)X
1509(the)X
1628(table)X
1805(may)X
1964(result.)X
2223(In)X
2311(addi-)X
720 4864(tion,)N
2 f
910(hsearch)X
1 f
1210(requires)X
1515(that)X
1681(the)X
1825(application)X
2226(allocate)X
720 4952(memory)N
1037(for)X
1181(the)X
1329(key)X
1495(and)X
1661(data)X
1845(items.)X
2108(Lastly,)X
2378(the)X
2 f
720 5040(hsearch)N
1 f
1013(routines)X
1310(provide)X
1594(no)X
1713(interface)X
2034(to)X
2135(store)X
2329(hash)X
720 5128(tables)N
927(on)X
1027(disk.)X
16 s
720 5593 MXY
864 0 Dl
2 f
8 s
760 5648(1)N
1 f
9 s
5673(UNIX)Y
990(is)X
1056(a)X
1106(registered)X
1408(trademark)X
1718(of)X
1796(AT&T.)X
10 s
2878 2128(The)N
3032(goal)X
3199(of)X
3295(our)X
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3625(was)X
3779(to)X
3870(design)X
4108(and)X
4253(imple-)X
2706 2216(ment)N
2900(a)X
2970(new)X
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3436(that)X
3590(provides)X
3899(a)X
3968(superset)X
4264(of)X
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2706 2304(functionality)N
3144(of)X
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2 f
3411(dbm)X
1 f
3578(and)X
2 f
3723(hsearch)X
1 f
3977(.)X
4045(The)X
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2706 2392(had)N
2871(to)X
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3348(the)X
3495(interface)X
3826(shortcomings)X
4306(cited)X
2706 2480(above)N
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3185(implementation)X
3719(had)X
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4238(perfor-)X
2706 2568(mance)N
2942(equal)X
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3235(superior)X
3524(to)X
3612(that)X
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3851(the)X
3975(existing)X
4253(imple-)X
2706 2656(mentations.)N
3152(In)X
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3913(a)X
4003(compact)X
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2706 2744(representation,)N
3224(graceful)X
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3729(growth,)X
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3033(time)X
3234(performance,)X
3720(we)X
3873(selected)X
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3551([LAR88,)X
3872(LIT80].)X
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3498(to)X
3586(handle)X
3826(page)X
4004(over\257ows)X
4346(and)X
2706 3096(large)N
2900(key)X
3049(handling)X
3362(with)X
3537(a)X
3606(single)X
3830(mechanism,)X
4248(named)X
2706 3184(buddy-in-waiting.)N
3 f
2975 3338(Existing)N
3274(UNIX)X
3499(Hashing)X
3802(Techniques)X
1 f
2878 3470(Over)N
3076(the)X
3210(last)X
3357(decade,)X
3637(several)X
3901(dynamic)X
4213(hashing)X
2706 3558(schemes)N
3000(have)X
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3348(developed)X
3700(for)X
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2706 3646(ing)N
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3767(inclusion)X
4107(of)X
2 f
4221(dbm)X
1 f
4359(,)X
4426(a)X
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3008(database)X
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3834(by)X
3950(Ken)X
4120(Thompson)X
2706 3822([THOM90],)N
3141(in)X
3248(the)X
3391(Seventh)X
3694(Edition)X
3974(UNIX)X
4220(system.)X
2706 3910(Since)N
2916(then,)X
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4032(same)X
4228(library,)X
2 f
2706 3998(ndbm)N
1 f
2884(,)X
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2 f
4273(sdbm)X
1 f
4442(,)X
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2706 4174(library)N
2 f
2950(gdbm)X
1 f
3128(,)X
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2829(Free)X
2997(Software)X
3312(Foundation's)X
3759(\(FSF\))X
3970(software)X
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1 f
2908(map)X
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2 f
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1 f
2921(uses)X
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2 f
4168(directory)X
1 f
2706 4904([ENB88])N
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3033(hsearch)X
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3317(routines)X
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1 f
2706 5458(is)N
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3901(,)X
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3 f
720 5960(USENIX)N
9 f
1042(-)X
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1106(Winter)X
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1562(Dallas,)X
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1 f
4424(1)X

2 p
%%Page: 2 2
10 s 10 xH 0 xS 1 f
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432 258(A)N
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1282(library)X
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1755(function)X
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432 1664(access)N
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877 1929(2)N
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1430(operation.)X
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1376(a)X
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1795(bitmap)X
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432 5200(tains)N
618(the)X
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2 f
7 s
5168(n)Y
9 f
1139(+)X
1 f
1170(1)X
2 f
10 s
9 f
5200(-)Y
1 f
1242(1)X
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1467(\(1)X
2 f
9 f
1534(+)X
1 f
1578(2)X
2 f
9 f
(+)S
1 f
1662(4)X
2 f
9 f
(+)S
1 f
1746(...)X
2 f
9 f
(+)S
1 f
1850(2)X
2 f
7 s
5168(n)Y
10 s
1 f
1931 5200(\))N
1992(which)X
432 5288(trace)N
649(the)X
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2 f
1050(split)X
1247(history)X
1 f
1529(of)X
1656(the)X
1813(addressable)X
16 s
432 5433 MXY
864 0 Dl
2 f
8 s
472 5488(2)N
1 f
9 s
523 5513(This)N
670(bit-randomizing)X
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1416(is)X
1482(important)X
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2052(radi-)X
432 5593(cally)N
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432 5673(in)N
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846(clustering)X
1148(of)X
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1526(in)X
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10 s
2418 538(buckets.)N
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4002(bit)X
4112(to)X
2418 828(consult)N
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3283(hash)X
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3973(exam-)X
2418 916(ined\).)N
2631(If)X
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2982(\(indicating)X
3356(that)X
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3628(bucket)X
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3684(hash)X
3851(value.)X
4085(As)X
2418 1092(bit)N
2525(n)X
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2662(revealed,)X
2977(a)X
3035(mask)X
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3422(to)X
3506(2)X
2 f
7 s
1060(n)Y
9 f
3583(+)X
1 f
3614(1)X
2 f
10 s
9 f
1092(-)Y
1 f
3686(1)X
3748(will)X
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2418 1180(current)N
2675(bucket)X
2918(address.)X
3228(Adding)X
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2 f
7 s
1148(n)Y
9 f
3573(+)X
1 f
3604(1)X
2 f
10 s
9 f
1180(-)Y
1 f
3676(1)X
3744(to)X
3834(the)X
3960(bucket)X
2418 1268(address)N
2701(identi\256es)X
3035(which)X
3272(bit)X
3397(in)X
3500(the)X
3639(bitmap)X
3902(must)X
4098(be)X
2418 1356(checked.)N
2743(We)X
2876(continue)X
3173(revealing)X
3493(bits)X
3628(of)X
3715(the)X
3833(hash)X
4000(value)X
2418 1444(until)N
2591(all)X
2698(set)X
2814(bits)X
2955(in)X
3043(the)X
3167(bitmap)X
3415(are)X
3540(exhausted.)X
3907(The)X
4058(fol-)X
2418 1532(lowing)N
2682(algorithm,)X
3055(a)X
3133(simpli\256cation)X
3614(of)X
3723(the)X
3863(algorithm)X
2418 1620(due)N
2565(to)X
2658(Ken)X
2823(Thompson)X
3196([THOM90,)X
3590(TOR88],)X
3908(uses)X
4076(the)X
2418 1708(hash)N
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2839(and)X
2995(the)X
3133(bitmap)X
3395(to)X
3497(calculate)X
3823(the)X
3960(bucket)X
2418 1796(address)N
2679(as)X
2766(discussed)X
3093(above.)X
0(Courier)xf 0 f
1 f
0 f
8 s
2418 2095(hash)N
2608(=)X
2684 -0.4038(calchash\(key\);)AX
2418 2183(mask)N
2608(=)X
2684(0;)X
2418 2271(while)N
2646 -0.4018(\(isbitset\(\(hash)AX
3254(&)X
3330(mask\))X
3558(+)X
3634(mask\)\))X
2706 2359(mask)N
2896(=)X
2972(\(mask)X
3200(<<)X
3314(1\))X
3428(+)X
3504(1;)X
2418 2447(bucket)N
2684(=)X
2760(hash)X
2950(&)X
3026(mask;)X
2 f
10 s
3211 2812(sdbm)N
1 f
2590 2944(The)N
2 f
2738(sdbm)X
1 f
2930(library)X
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3243(a)X
3302(public-domain)X
3791(clone)X
3987(of)X
4076(the)X
2 f
2418 3032(ndbm)N
1 f
2638(library,)X
2914(developed)X
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3620(Yigit)X
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2 f
2418 3120(ndbm)N
1 f
2596('s)X
2692(functionality)X
3139(under)X
3359(some)X
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3973(UNIX)X
2418 3208(that)N
2559(exclude)X
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3317(reasons)X
3578([YIG89].)X
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2735(interface,)X
3064(and)X
3207(the)X
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3524(structure)X
3832(of)X
2 f
3926(sdbm)X
1 f
4121(is)X
2418 3384(identical)N
2733(to)X
2 f
2834(ndbm)X
1 f
3051(but)X
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3723(of)X
3828(the)X
2 f
3964(access)X
1 f
2418 3472(function,)N
2726(such)X
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3474(of)X
3561(the)X
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3913(address,)X
2418 3560(and)N
2563(the)X
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2418 3648(incompatible)N
2856(at)X
2934(the)X
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3349(level.)X
2590 3762(The)N
2 f
2740(sdbm)X
1 f
2934(library)X
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3251(based)X
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3622(simpli\256ed)X
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2778(of)X
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2 f
3406(dynamic)X
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1 f
4009(algo-)X
2418 3938(rithm)N
2616(including)X
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2 f
3066(re\256nements)X
3461(and)X
3605(variations)X
1 f
3953(of)X
4044(sec-)X
2418 4026(tion)N
2562(5)X
2622([LAR78].)X
2956(Larson's)X
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4024(for)X
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2418 4114(forest)N
2635(of)X
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3941(by)X
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2586(functions.)X
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2418 4378(which)N
2659(is)X
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3377(boolean)X
3675(pseudo-random)X
2418 4466(number)N
2687(generator)X
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2418 4554(traverse)N
2733(the)X
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3070(until)X
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3579(\(split\))X
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2418 4642(exhausted)N
2763(and)X
2903(an)X
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3827(is)X
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2571(bucket)X
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2418 5108(that)N
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3392(and)X
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3536(trie.)X
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3944(1)X
4010(illus-)X
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3831(with)X
3994(them.)X
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3768(each)X
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4112(to)X
2418 5548(refer)N
2594(to)X
2679(a)X
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3279(These)X
3494(bucket)X
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2990(trie)X
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3691(subtries)X
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3 f
432 5960(2)N
2970(USENIX)X
9 f
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3621('91)X
9 f
3748(-)X
3 f
3812(Dallas,)X
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3 p
%%Page: 3 3
0(Courier)xf 0 f
10 s 10 xH 0 xS 0 f
3 f
720 258(Seltzer)N
977(&)X
1064(Yigit)X
3278(A)X
3356(New)X
3528(Hashing)X
3831(Package)X
4136(for)X
4259(UNIX)X
1 f
720 538(live)N
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1092(existed)X
1340([KNU68].)X
1709(For)X
1841(example,)X
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2432(F)X
720 626(and)N
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1787(C,)X
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1101(reside)X
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1714(that)X
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1552(G)X
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2033(children.)X
10 f
720 890 -0.0930(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)AN
3 f
1894 2247(L1)N
784 1925(A)N
1431(E)X
1106 2247(D)N
1428 1281(C)N
1109 1603(B)N
1884 1930(L01)N
1879 1286(L00)N
1221 1814(1)N
903 2131(1)N
1221 1402(0)N
903 1714(0)N
1 Dt
1397 1821 MXY
-8 -32 Dl
-5 19 Dl
-20 6 Dl
33 7 Dl
-187 -182 Dl
1397 1322 MXY
-33 7 Dl
20 6 Dl
5 19 Dl
8 -32 Dl
-187 182 Dl
1069 1639 MXY
-32 7 Dl
20 6 Dl
5 19 Dl
7 -32 Dl
-186 182 Dl
1374 1891 MXY
185 Dc
1779 2133 MXY
0 161 Dl
322 0 Dl
0 -161 Dl
-322 0 Dl
1811 MY
0 161 Dl
322 0 Dl
0 -161 Dl
-322 0 Dl
1166 MY
0 161 Dl
322 0 Dl
0 -161 Dl
-322 0 Dl
1052 2213 MXY
185 Dc
1569 MY
185 Dc
720 1881 MXY
185 Dc
1779 2213 MXY
-28 -17 Dl
10 17 Dl
-10 18 Dl
28 -18 Dl
-543 0 Dl
1769 1891 MXY
-28 -18 Dl
10 18 Dl
-10 18 Dl
28 -18 Dl
-201 0 Dl
1364 1247 MXY
185 Dc
1769 MX
-28 -18 Dl
10 18 Dl
-10 18 Dl
28 -18 Dl
-201 0 Dl
1064 2143 MXY
-7 -32 Dl
-5 19 Dl
-20 6 Dl
32 7 Dl
-181 -181 Dl
3 Dt
-1 Ds
8 s
720 2482(Figure)N
925(1:)X
1 f
1002(Radix)X
1179(search)X
1365(trie)X
1474(with)X
1612(internal)X
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2004(A)X
2074(and)X
2189(B,)X
2271(external)X
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1819(stored)X
1997(in)X
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2370(por-)X
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10 s
10 f
720 2922 -0.0930(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)AN
1 f
892 3124(Further)N
1153(simpli\256cations)X
1647(of)X
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2076([YIG89])X
2377(are)X
720 3212(possible.)N
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1564(radix)X
1765(trie)X
1908(to)X
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2219(the)X
2352(\256rst)X
720 3300(hash)N
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1562(the)X
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2231(number)X
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1404(trie)X
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1969(a)X
2042(direct)X
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720 3652(address)N
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2 f
1424(access)X
1 f
1663(function)X
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2 f
8 s
1166 3891(3)N
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10 s
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7 s
3884(th)Y
10 s
1 f
1791 3916(bit.)N
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8 s
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1768(+)X
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1 f
16 s
720 5353 MXY
864 0 Dl
2 f
8 s
760 5408(3)N
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9 s
818 5433(A)N
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8 s
3146 538(/*)N
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3754(+)X
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2 f
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3495 1167(gdbm)N
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1 f
3697(libraries)X
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21 -13 Dl
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0 -88 Dl
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8 13 Dl
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6 p
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2817 MX
 2817 2275 lineto
 2950 2275 lineto
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 2817 2408 lineto
 2817 2275 lineto
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2684 MX
 2684 2275 lineto
 2817 2275 lineto
 2817 2408 lineto
 2684 2408 lineto
 2684 2275 lineto
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3615 MX
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2950 MX
0 133 Dl
266 0 Dl
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6 16 Dl
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27 1 Dl
-14 -8 Dl
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27 7 Dl
-13 -11 Dl
3 -17 Dl
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3 Dt
-1 Ds
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10 f
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1 Dt
2309 3177 MXY
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789 3160 MXY
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789 3091 MXY
-24 -15 Dl
9 15 Dl
-9 15 Dl
24 -15 Dl
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2309 3125 MXY
104 0 Dl
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927 3160 MXY
24 15 Dl
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9 -15 Dl
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553 0 Dl
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8 27 Dl
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16 -6 Dl
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138 121 Dl
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28 3 Dl
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1 -18 Dl
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3108 MY
-28 -3 Dl
15 10 Dl
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14 -24 Dl
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-8 -27 Dl
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1480 MX
-24 -15 Dl
9 15 Dl
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3 f
5 s
1083 3073(LRU)N
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1445 3747(Over\257ow)N
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0 69 Dl
1756 MX
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3 Dt
1756 3419 MXY
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27 6 Dl
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15 -24 Dl
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1549 MX
15 -24 Dl
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858 3471 MXY
15 -24 Dl
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15 -24 Dl
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15 -24 Dl
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858 3056 MXY
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1 Dt
2171 3471 MXY
 2171 3471 lineto
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789 MX
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1756 3194 MXY
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1480 MX
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789 MX
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2780 MY
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927 MX
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1065 MX
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1203 MX
0 138 Dl
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1342 MX
0 138 Dl
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1480 MX
0 138 Dl
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1618 MX
0 138 Dl
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0 -138 Dl
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1756 MX
0 138 Dl
139 0 Dl
0 -138 Dl
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1895 MX
0 138 Dl
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0 -138 Dl
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2033 MX
0 138 Dl
138 0 Dl
0 -138 Dl
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2171 MX
0 138 Dl
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2309 MX
0 138 Dl
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13 s
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8 p
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432 802 -0.0930(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)AN
619 2380 MXY
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629 2437 MXY
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648 2504 MXY
-12 25 Dl
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686 2515 MXY
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762 2516 MXY
-12 24 Dl
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916 2515 MXY
-13 24 Dl
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1222 2516 MXY
-12 24 Dl
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1834 2515 MXY
-12 24 Dl
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1 Dt
619 2392 MXY
10 57 Dl
19 67 Dl
38 11 Dl
76 1 Dl
154 -1 Dl
306 1 Dl
612 -1 Dl
8 s
1 f
1628 2522(128)N
3 Dt
607 2245 MXY
24 Dc
617 2375 MXY
23 Dc
635 2442 MXY
24 Dc
674 2525 MXY
23 Dc
750 2529 MXY
24 Dc
904 2527 MXY
23 Dc
1210 MX
23 Dc
1822 2528 MXY
23 Dc
20 Ds
1 Dt
619 2245 MXY
10 130 Dl
19 67 Dl
38 83 Dl
76 4 Dl
154 -2 Dl
306 0 Dl
612 1 Dl
678 2482(256)N
-1 Ds
3 Dt
619 2127 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
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629 2191 MXY
0 25 Dl
0 -12 Dl
12 0 Dl
-24 0 Dl
648 2334 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
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686 2409 MXY
0 25 Dl
0 -13 Dl
12 0 Dl
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762 2516 MXY
0 25 Dl
0 -12 Dl
13 0 Dl
-25 0 Dl
916 2516 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
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1222 2515 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
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1834 2515 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
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5 Dt
619 2139 MXY
10 65 Dl
19 142 Dl
38 75 Dl
76 108 Dl
154 -1 Dl
306 -1 Dl
612 0 Dl
694 2401(512)N
3 Dt
631 2064 MXY
-24 24 Dl
12 -12 Dl
-12 -12 Dl
24 24 Dl
641 2077 MXY
-24 25 Dl
12 -12 Dl
-12 -13 Dl
24 25 Dl
660 2132 MXY
-24 24 Dl
12 -12 Dl
-12 -12 Dl
24 24 Dl
698 2292 MXY
-24 24 Dl
12 -12 Dl
-12 -12 Dl
24 24 Dl
775 2382 MXY
-25 24 Dl
12 -12 Dl
-12 -12 Dl
25 24 Dl
928 2516 MXY
-25 24 Dl
13 -12 Dl
-13 -12 Dl
25 24 Dl
1234 2516 MXY
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12 -12 Dl
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24 25 Dl
1846 2516 MXY
-24 24 Dl
12 -12 Dl
-12 -12 Dl
24 24 Dl
16 Ds
1 Dt
619 2076 MXY
10 14 Dl
19 54 Dl
38 160 Dl
76 90 Dl
154 134 Dl
306 1 Dl
612 -1 Dl
694 2257(1024)N
-1 Ds
3 Dt
619 1877 MXY
12 -24 Dl
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629 1855 MXY
12 -24 Dl
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648 1838 MXY
12 -24 Dl
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12 24 Dl
686 1860 MXY
12 -25 Dl
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12 25 Dl
762 1923 MXY
13 -24 Dl
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12 24 Dl
916 2087 MXY
12 -24 Dl
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13 24 Dl
1222 2256 MXY
12 -24 Dl
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12 24 Dl
1834 2541 MXY
12 -25 Dl
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12 25 Dl
619 1865 MXY
10 -22 Dl
19 -17 Dl
38 21 Dl
76 64 Dl
154 164 Dl
306 169 Dl
612 285 Dl
1645 2427(4096)N
619 1243 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
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629 1196 MXY
0 24 Dl
0 -12 Dl
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648 1146 MXY
0 24 Dl
0 -12 Dl
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686 1174 MXY
0 25 Dl
0 -13 Dl
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762 1249 MXY
0 24 Dl
0 -12 Dl
13 0 Dl
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916 1371 MXY
0 24 Dl
0 -12 Dl
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1222 1680 MXY
0 24 Dl
0 -12 Dl
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1834 1999 MXY
0 24 Dl
0 -12 Dl
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619 1255 MXY
10 -47 Dl
19 -50 Dl
38 28 Dl
76 75 Dl
154 122 Dl
306 309 Dl
612 319 Dl
1741 1934(8192)N
5 Dt
609 2531 MXY
1225 0 Dl
609 MX
0 -1553 Dl
2531 MY
0 16 Dl
4 Ds
1 Dt
2531 MY
0 -1553 Dl
593 2625(0)N
-1 Ds
5 Dt
916 2531 MXY
0 16 Dl
4 Ds
1 Dt
2531 MY
0 -1553 Dl
884 2625(32)N
-1 Ds
5 Dt
1222 2531 MXY
0 16 Dl
4 Ds
1 Dt
2531 MY
0 -1553 Dl
1190 2625(64)N
-1 Ds
5 Dt
1528 2531 MXY
0 16 Dl
4 Ds
1 Dt
2531 MY
0 -1553 Dl
1496 2625(96)N
-1 Ds
5 Dt
1834 2531 MXY
0 16 Dl
4 Ds
1 Dt
2531 MY
0 -1553 Dl
1786 2625(128)N
-1 Ds
5 Dt
609 2531 MXY
-16 0 Dl
4 Ds
1 Dt
609 MX
1225 0 Dl
545 2558(0)N
-1 Ds
5 Dt
609 2013 MXY
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4 Ds
1 Dt
609 MX
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481 2040(100)N
-1 Ds
5 Dt
609 1496 MXY
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4 Ds
1 Dt
609 MX
1225 0 Dl
481 1523(200)N
-1 Ds
5 Dt
609 978 MXY
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4 Ds
1 Dt
609 MX
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481 1005(300)N
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3 Dt
-1 Ds
3 f
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8 s
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4 Ds
1 Dt
666 3410 MXY
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-1 Ds
5 Dt
666 MX
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506 3825(2400)N
4 Ds
1 Dt
666 3799 MXY
1168 0 Dl
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5 Dt
666 MX
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506 4214(1600)N
4 Ds
1 Dt
666 4186 MXY
1168 0 Dl
-1 Ds
5 Dt
666 MX
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538 4602(800)N
4 Ds
1 Dt
666 4575 MXY
1168 0 Dl
-1 Ds
5 Dt
666 MX
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602 4990(0)N
4 Ds
1 Dt
666 4963 MXY
1168 0 Dl
-1 Ds
5 Dt
666 MX
-16 0 Dl
1786 5057(128)N
4 Ds
1 Dt
1834 4963 MXY
0 -1553 Dl
-1 Ds
5 Dt
4963 MY
0 16 Dl
1510 5057(96)N
4 Ds
1 Dt
1542 4963 MXY
0 -1553 Dl
-1 Ds
5 Dt
4963 MY
0 16 Dl
1218 5057(64)N
4 Ds
1 Dt
1250 4963 MXY
0 -1553 Dl
-1 Ds
5 Dt
4963 MY
0 16 Dl
926 5057(32)N
4 Ds
1 Dt
958 4963 MXY
0 -1553 Dl
-1 Ds
5 Dt
4963 MY
0 16 Dl
650 5057(0)N
4 Ds
1 Dt
666 4963 MXY
0 -1553 Dl
-1 Ds
5 Dt
4963 MY
0 16 Dl
4963 MY
0 -1553 Dl
4963 MY
1168 0 Dl
1741 4752(8192)N
3 Dt
675 3732 MXY
9 -172 Dl
18 -118 Dl
37 128 Dl
73 -121 Dl
146 623 Dl
292 497 Dl
584 245 Dl
4802 MY
0 24 Dl
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1250 4557 MXY
0 25 Dl
0 -13 Dl
12 0 Dl
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958 4060 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
-24 0 Dl
812 3437 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
-24 0 Dl
739 3558 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
-24 0 Dl
702 3430 MXY
0 25 Dl
0 -13 Dl
13 0 Dl
-25 0 Dl
684 3548 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
-24 0 Dl
675 3720 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
-24 0 Dl
1637 4912(4096)N
675 4307 MXY
9 -58 Dl
18 30 Dl
37 89 Dl
73 144 Dl
146 235 Dl
292 122 Dl
584 89 Dl
4970 MY
12 -24 Dl
-24 0 Dl
12 24 Dl
1250 4881 MXY
12 -24 Dl
-24 0 Dl
12 24 Dl
958 4759 MXY
12 -24 Dl
-24 0 Dl
12 24 Dl
812 4524 MXY
12 -24 Dl
-24 0 Dl
12 24 Dl
739 4380 MXY
12 -24 Dl
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12 24 Dl
702 4291 MXY
13 -24 Dl
-25 0 Dl
12 24 Dl
684 4261 MXY
12 -24 Dl
-24 0 Dl
12 24 Dl
675 4319 MXY
12 -24 Dl
-24 0 Dl
12 24 Dl
734 4662(1024)N
16 Ds
1 Dt
675 4352 MXY
9 60 Dl
18 134 Dl
37 266 Dl
73 117 Dl
146 30 Dl
292 0 Dl
584 -1 Dl
-1 Ds
3 Dt
1846 4946 MXY
-24 24 Dl
12 -12 Dl
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24 24 Dl
1262 4946 MXY
-24 25 Dl
12 -12 Dl
-12 -13 Dl
24 25 Dl
970 4947 MXY
-24 24 Dl
12 -12 Dl
-12 -12 Dl
24 24 Dl
824 4917 MXY
-24 24 Dl
12 -12 Dl
-12 -12 Dl
24 24 Dl
751 4800 MXY
-24 24 Dl
12 -12 Dl
-12 -12 Dl
24 24 Dl
715 4534 MXY
-25 25 Dl
12 -13 Dl
-12 -12 Dl
25 25 Dl
696 4400 MXY
-24 24 Dl
12 -12 Dl
-12 -12 Dl
24 24 Dl
687 4339 MXY
-24 25 Dl
12 -12 Dl
-12 -13 Dl
24 25 Dl
718 4792(512)N
5 Dt
675 4422 MXY
9 137 Dl
18 278 Dl
37 105 Dl
73 18 Dl
146 -1 Dl
292 0 Dl
584 -1 Dl
3 Dt
4946 MY
0 24 Dl
0 -12 Dl
12 0 Dl
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1250 4946 MXY
0 25 Dl
0 -12 Dl
12 0 Dl
-24 0 Dl
958 4947 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
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812 4948 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
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739 4930 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
-24 0 Dl
702 4824 MXY
0 25 Dl
0 -12 Dl
13 0 Dl
-25 0 Dl
684 4547 MXY
0 24 Dl
0 -12 Dl
12 0 Dl
-24 0 Dl
675 4410 MXY
0 25 Dl
0 -13 Dl
12 0 Dl
-24 0 Dl
750 4921(256)N
20 Ds
1 Dt
675 4597 MXY
9 246 Dl
18 106 Dl
37 10 Dl
73 0 Dl
146 0 Dl
292 0 Dl
584 -1 Dl
-1 Ds
3 Dt
1822 MX
23 Dc
1238 4959 MXY
23 Dc
946 MX
23 Dc
800 MX
23 Dc
727 MX
23 Dc
691 4949 MXY
23 Dc
672 4843 MXY
24 Dc
663 4597 MXY
24 Dc
1395 4961(128)N
1 Dt
675 4855 MXY
9 93 Dl
18 10 Dl
37 1 Dl
73 0 Dl
146 -1 Dl
292 0 Dl
584 0 Dl
3 Dt
4946 MY
-12 24 Dl
24 0 Dl
-12 -24 Dl
1250 MX
-12 24 Dl
24 0 Dl
-12 -24 Dl
958 MX
-12 24 Dl
24 0 Dl
-12 -24 Dl
812 MX
-12 25 Dl
24 0 Dl
-12 -25 Dl
739 4947 MXY
-12 24 Dl
24 0 Dl
-12 -24 Dl
702 4946 MXY
-12 24 Dl
25 0 Dl
-13 -24 Dl
684 4936 MXY
-12 24 Dl
24 0 Dl
-12 -24 Dl
675 4843 MXY
-12 24 Dl
24 0 Dl
-12 -24 Dl
3 Dt
-1 Ds
3 f
432 5314(Figure)N
634(5b:)X
1 f
744(Elapsed)X
967(Time)X
1123(for)X
1218(dictionary)X
1498(data)X
1625(set)X
1717(with)X
1851(1M)X
1960(of)X
2033(buffer)X
432 5402(space)N
593(and)X
705(varying)X
920(bucket)X
1110(sizes)X
1254(and)X
1366(\256ll)X
1457(factors.)X
1681(Each)X
1827(line)X
1942(is)X
2004(labeled)X
432 5490(with)N
562(its)X
639(bucket)X
825(size.)X
10 s
2590 538(If)N
2677(an)X
2785(approximation)X
3284(of)X
3383(the)X
3513(number)X
3790(of)X
3889(elements)X
2418 626(ultimately)N
2773(to)X
2866(be)X
2973(stored)X
3200(in)X
3293(the)X
3422(hash)X
3599(table)X
3785(is)X
3868(known)X
4116(at)X
2418 714(the)N
2564(time)X
2754(of)X
2869(creation,)X
3196(the)X
3342(hash)X
3536(package)X
3847(takes)X
4059(this)X
2418 802(number)N
2688(as)X
2779(a)X
2839(parameter)X
3185(and)X
3325(uses)X
3487(it)X
3555(to)X
3641(hash)X
3812(entries)X
4050(into)X
2418 890(the)N
2541(full)X
2677(sized)X
2867(table)X
3048(rather)X
3261(than)X
3424(growing)X
3716(the)X
3838(table)X
4018(from)X
2418 978(a)N
2477(single)X
2691(bucket.)X
2968(If)X
3044(this)X
3181(number)X
3448(is)X
3523(not)X
3647(known,)X
3907(the)X
4027(hash)X
2418 1066(table)N
2632(starts)X
2859(with)X
3059(a)X
3153(single)X
3402(bucket)X
3674(and)X
3848(gracefully)X
2418 1154(expands)N
2707(as)X
2800(elements)X
3111(are)X
3236(added,)X
3474(although)X
3780(a)X
3842(slight)X
4044(per-)X
2418 1242(formance)N
2747(degradation)X
3151(may)X
3313(be)X
3413(noticed.)X
3713(Figure)X
3946(6)X
4010(illus-)X
2418 1330(trates)N
2625(the)X
2756(difference)X
3116(in)X
3211(performance)X
3651(between)X
3952(storing)X
2418 1418(keys)N
2588(in)X
2673(a)X
2732(\256le)X
2857(when)X
3054(the)X
3174(ultimate)X
3458(size)X
3605(is)X
3680(known)X
3920(\(the)X
4067(left)X
2418 1506(bars)N
2581(in)X
2672(each)X
2849(set\),)X
3014(compared)X
3360(to)X
3450(building)X
3744(the)X
3870(\256le)X
4000(when)X
2418 1594(the)N
2550(ultimate)X
2846(size)X
3005(is)X
3091(unknown)X
3422(\(the)X
3580(right)X
3764(bars)X
3931(in)X
4026(each)X
2418 1682(set\).)N
2609(Once)X
2814(the)X
2947(\256ll)X
3069(factor)X
3291(is)X
3378(suf\256ciently)X
3772(high)X
3948(for)X
4076(the)X
2418 1770(page)N
2596(size)X
2747(\(8\),)X
2887(growing)X
3180(the)X
3304(table)X
3486(dynamically)X
3908(does)X
4081(lit-)X
2418 1858(tle)N
2518(to)X
2600(degrade)X
2875(performance.)X
10 f
2418 1946 -0.0930(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)AN
9 s
1 f
2413 3238(s)N
2409 3173(d)N
2409 3108(n)N
2409 3043(o)N
2411 2979(c)N
2411 2914(e)N
2407 2849(S)N
3143 4129(Fill)N
3261(Factor)X
2448 2152(15)N
4 Ds
1 Dt
2557 2122 MXY
1473 0 Dl
-1 Ds
5 Dt
2557 MX
-19 0 Dl
2448 2747(10)N
4 Ds
1 Dt
2557 2717 MXY
1473 0 Dl
-1 Ds
5 Dt
2557 MX
-19 0 Dl
2484 3343(5)N
4 Ds
1 Dt
2557 3313 MXY
1473 0 Dl
-1 Ds
5 Dt
2557 MX
-19 0 Dl
2484 3938(0)N
4 Ds
1 Dt
2557 3908 MXY
1473 0 Dl
-1 Ds
5 Dt
2557 MX
-19 0 Dl
3976 4015(128)N
4 Ds
1 Dt
4030 3908 MXY
0 -1786 Dl
-1 Ds
5 Dt
3908 MY
0 19 Dl
3626 4015(96)N
4 Ds
1 Dt
3662 3908 MXY
0 -1786 Dl
-1 Ds
5 Dt
3908 MY
0 19 Dl
3258 4015(64)N
4 Ds
1 Dt
3294 3908 MXY
0 -1786 Dl
-1 Ds
5 Dt
3908 MY
0 19 Dl
2889 4015(32)N
4 Ds
1 Dt
2925 3908 MXY
0 -1786 Dl
-1 Ds
5 Dt
3908 MY
0 19 Dl
2539 4015(0)N
4 Ds
1 Dt
2557 3908 MXY
0 -1786 Dl
-1 Ds
5 Dt
3908 MY
0 19 Dl
3908 MY
0 -1786 Dl
3908 MY
1473 0 Dl
4053 2378(8192)N
3 Dt
2569 2277 MXY
11 0 Dl
23 48 Dl
46 -167 Dl
92 35 Dl
184 12 Dl
369 143 Dl
736 0 Dl
2334 MY
0 28 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
3294 2334 MXY
0 28 Dl
0 -14 Dl
13 0 Dl
-27 0 Dl
2925 2192 MXY
0 27 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
2741 2180 MXY
0 27 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
2649 2144 MXY
0 28 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
2603 2311 MXY
0 27 Dl
0 -13 Dl
14 0 Dl
-28 0 Dl
2580 2263 MXY
0 28 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
2569 2263 MXY
0 28 Dl
0 -14 Dl
13 0 Dl
-27 0 Dl
4053 2591(4096)N
2569 2348 MXY
11 -11 Dl
23 -96 Dl
46 71 Dl
92 72 Dl
184 226 Dl
369 48 Dl
736 -60 Dl
2612 MY
14 -28 Dl
-28 0 Dl
14 28 Dl
3294 2672 MXY
13 -28 Dl
-27 0 Dl
14 28 Dl
2925 2624 MXY
14 -28 Dl
-28 0 Dl
14 28 Dl
2741 2398 MXY
14 -28 Dl
-28 0 Dl
14 28 Dl
2649 2326 MXY
14 -27 Dl
-28 0 Dl
14 27 Dl
2603 2255 MXY
14 -28 Dl
-28 0 Dl
14 28 Dl
2580 2350 MXY
14 -27 Dl
-28 0 Dl
14 27 Dl
2569 2362 MXY
13 -28 Dl
-27 0 Dl
14 28 Dl
4053 2681(1024)N
16 Ds
1 Dt
2569 2300 MXY
11 48 Dl
23 96 Dl
46 95 Dl
92 274 Dl
184 202 Dl
369 -155 Dl
736 -190 Dl
-1 Ds
3 Dt
4044 2656 MXY
-28 28 Dl
14 -14 Dl
-14 -14 Dl
28 28 Dl
3307 2846 MXY
-27 28 Dl
14 -14 Dl
-14 -14 Dl
27 28 Dl
2939 3001 MXY
-28 28 Dl
14 -14 Dl
-14 -14 Dl
28 28 Dl
2755 2799 MXY
-28 28 Dl
14 -14 Dl
-14 -14 Dl
28 28 Dl
2663 2525 MXY
-28 28 Dl
14 -14 Dl
-14 -14 Dl
28 28 Dl
2617 2430 MXY
-28 28 Dl
14 -14 Dl
-14 -14 Dl
28 28 Dl
2594 2334 MXY
-28 28 Dl
14 -14 Dl
-14 -14 Dl
28 28 Dl
2582 2287 MXY
-27 27 Dl
14 -14 Dl
-14 -13 Dl
27 27 Dl
4053 2851(512)N
5 Dt
2569 2372 MXY
11 -24 Dl
23 405 Dl
46 83 Dl
92 227 Dl
184 -72 Dl
369 -119 Dl
736 -107 Dl
3 Dt
2751 MY
0 28 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
3294 2858 MXY
0 28 Dl
0 -14 Dl
13 0 Dl
-27 0 Dl
2925 2977 MXY
0 28 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
2741 3049 MXY
0 27 Dl
0 -13 Dl
14 0 Dl
-28 0 Dl
2649 2823 MXY
0 27 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
2603 2739 MXY
0 28 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
2580 2334 MXY
0 28 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
2569 2358 MXY
0 28 Dl
0 -14 Dl
13 0 Dl
-27 0 Dl
4053 2795(256)N
20 Ds
1 Dt
2569 2456 MXY
11 285 Dl
23 95 Dl
46 251 Dl
92 -60 Dl
184 -84 Dl
369 -107 Dl
736 -71 Dl
-1 Ds
3 Dt
4016 MX
27 Dc
3280 2836 MXY
27 Dc
2912 2943 MXY
27 Dc
2728 3027 MXY
27 Dc
2635 3087 MXY
28 Dc
2589 2836 MXY
28 Dc
2566 2741 MXY
27 Dc
2554 2456 MXY
28 Dc
4053 2741(128)N
1 Dt
2569 2729 MXY
11 203 Dl
23 131 Dl
46 -60 Dl
92 -119 Dl
184 -60 Dl
369 -83 Dl
736 -12 Dl
3 Dt
2716 MY
-14 27 Dl
28 0 Dl
-14 -27 Dl
3294 2727 MXY
-14 28 Dl
27 0 Dl
-13 -28 Dl
2925 2811 MXY
-14 27 Dl
28 0 Dl
-14 -27 Dl
2741 2870 MXY
-14 28 Dl
28 0 Dl
-14 -28 Dl
2649 2989 MXY
-14 28 Dl
28 0 Dl
-14 -28 Dl
2603 3049 MXY
-14 27 Dl
28 0 Dl
-14 -27 Dl
2580 2918 MXY
-14 28 Dl
28 0 Dl
-14 -28 Dl
2569 2716 MXY
-14 27 Dl
27 0 Dl
-13 -27 Dl
3 Dt
-1 Ds
3 f
8 s
2418 4286(Figure)N
2628(5c:)X
1 f
2738(User)X
2887(Time)X
3051(for)X
3154(dictionary)X
3442(data)X
3577(set)X
3677(with)X
3820(1M)X
3938(of)X
4019(buffer)X
2418 4374(space)N
2579(and)X
2691(varying)X
2906(bucket)X
3096(sizes)X
3240(and)X
3352(\256ll)X
3443(factors.)X
3667(Each)X
3813(line)X
3928(is)X
3990(labeled)X
2418 4462(with)N
2548(its)X
2625(bucket)X
2811(size.)X
10 s
10 f
2418 4638 -0.0930(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)AN
1 f
2590 4840(Since)N
2796(no)X
2904(known)X
3150(hash)X
3325(function)X
3620(performs)X
3938(equally)X
2418 4928(well)N
2589(on)X
2702(all)X
2815(possible)X
3110(data,)X
3297(the)X
3428(user)X
3595(may)X
3766(\256nd)X
3923(that)X
4076(the)X
2418 5016(built-in)N
2678(hash)X
2849(function)X
3140(does)X
3311(poorly)X
3544(on)X
3648(a)X
3708(particular)X
4040(data)X
2418 5104(set.)N
2548(In)X
2636(this)X
2771(case,)X
2950(a)X
3006(hash)X
3173(function,)X
3480(taking)X
3700(two)X
3840(arguments)X
2418 5192(\(a)N
2507(pointer)X
2760(to)X
2848(a)X
2910(byte)X
3074(string)X
3282(and)X
3424(a)X
3486(length\))X
3739(and)X
3880(returning)X
2418 5280(an)N
2517(unsigned)X
2829(long)X
2993(to)X
3077(be)X
3175(used)X
3344(as)X
3433(the)X
3553(hash)X
3722(value,)X
3938(may)X
4098(be)X
2418 5368(speci\256ed)N
2731(at)X
2817(hash)X
2992(table)X
3176(creation)X
3463(time.)X
3673(When)X
3893(an)X
3996(exist-)X
2418 5456(ing)N
2570(hash)X
2767(table)X
2973(is)X
3076(opened)X
3358(and)X
3524(a)X
3609(hash)X
3805(function)X
4121(is)X
2418 5544(speci\256ed,)N
2752(the)X
2879(hash)X
3054(package)X
3346(will)X
3498(try)X
3615(to)X
3705(determine)X
4054(that)X
2418 5632(the)N
2546(hash)X
2723(function)X
3020(supplied)X
3321(is)X
3404(the)X
3532(one)X
3678(with)X
3850(which)X
4076(the)X
2418 5720(table)N
2630(was)X
2811(created.)X
3139(There)X
3382(are)X
3536(a)X
3627(variety)X
3905(of)X
4027(hash)X
3 f
432 5960(8)N
2970(USENIX)X
9 f
3292(-)X
3 f
3356(Winter)X
3621('91)X
9 f
3748(-)X
3 f
3812(Dallas,)X
4065(TX)X

9 p
%%Page: 9 9
0(Courier)xf 0 f
10 s 10 xH 0 xS 0 f
3 f
720 258(Seltzer)N
977(&)X
1064(Yigit)X
3278(A)X
3356(New)X
3528(Hashing)X
3831(Package)X
4136(for)X
4259(UNIX)X
1 f
720 538(functions)N
1065(provided)X
1397(with)X
1586(the)X
1731(package.)X
2082(The)X
2253(default)X
720 626(function)N
1014(for)X
1135(the)X
1260(package)X
1551(is)X
1631(the)X
1755(one)X
1897(which)X
2119(offered)X
2378(the)X
720 714(best)N
875(performance)X
1308(in)X
1396(terms)X
1600(of)X
1693(cycles)X
1920(executed)X
2232(per)X
2360(call)X
720 802(\(it)N
827(did)X
965(not)X
1103(produce)X
1398(the)X
1531(fewest)X
1776(collisions)X
2117(although)X
2432(it)X
720 890(was)N
866(within)X
1091(a)X
1148(small)X
1341(percentage)X
1710(of)X
1797(the)X
1915(function)X
2202(that)X
2342(pro-)X
720 978(duced)N
947(the)X
1080(fewest)X
1324(collisions\).)X
1731(Again,)X
1981(in)X
2077(time)X
2253(critical)X
720 1066(applications,)N
1152(users)X
1342(are)X
1466(encouraged)X
1862(to)X
1949(experiment)X
2334(with)X
720 1154(a)N
783(variety)X
1032(of)X
1125(hash)X
1298(functions)X
1622(to)X
1710(achieve)X
1982(optimal)X
2252(perfor-)X
720 1242(mance.)N
10 f
720 1330 -0.0930(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)AN
3 f
7 s
1038 2925(Full)N
1149(size)X
1251(table)X
1384(\(left\))X
1547 2718(Fill)N
1643(Factor)X
2268 2662(64)N
1964(32)X
1674(16)X
1384(8)X
1093(4)X
4 Ds
1 Dt
900 2280 MXY
1548 0 Dl
900 1879 MXY
1548 0 Dl
900 1506 MXY
1548 0 Dl
1563 2902 MXY
111 0 Dl
-1 Ds
900 MX
110 0 Dl
1425 2828(System)N
983(User)X
1895 2778 MXY
 1895 2778 lineto
 1950 2778 lineto
 1950 2833 lineto
 1895 2833 lineto
 1895 2778 lineto
closepath 21 1895 2778 1950 2833 Dp
1342 MX
 1342 2778 lineto
 1397 2778 lineto
 1397 2833 lineto
 1342 2833 lineto
 1342 2778 lineto
closepath 14 1342 2778 1397 2833 Dp
900 MX
 900 2778 lineto
 955 2778 lineto
 955 2833 lineto
 900 2833 lineto
 900 2778 lineto
closepath 3 900 2778 955 2833 Dp
5 Dt
2283 2211 MXY
96 0 Dl
1992 MX
97 0 Dl
1702 MX
97 0 Dl
1411 2252 MXY
97 0 Dl
4 Ds
1 Dt
2283 2211 MXY
 2283 2211 lineto
 2379 2211 lineto
 2379 2252 lineto
 2283 2252 lineto
 2283 2211 lineto
closepath 14 2283 2211 2379 2252 Dp
1992 MX
 1992 2211 lineto
 2089 2211 lineto
 2089 2252 lineto
 1992 2252 lineto
 1992 2211 lineto
closepath 14 1992 2211 2089 2252 Dp
1702 MX
 1702 2211 lineto
 1799 2211 lineto
 1799 2252 lineto
 1702 2252 lineto
 1702 2211 lineto
closepath 14 1702 2211 1799 2252 Dp
1411 2252 MXY
 1411 2252 lineto
 1508 2252 lineto
 1508 2294 lineto
 1411 2294 lineto
 1411 2252 lineto
closepath 14 1411 2252 1508 2294 Dp
2283 MX
 2283 2252 lineto
 2379 2252 lineto
 2379 2612 lineto
 2283 2612 lineto
 2283 2252 lineto
closepath 3 2283 2252 2379 2612 Dp
1992 MX
 1992 2252 lineto
 2089 2252 lineto
 2089 2612 lineto
 1992 2612 lineto
 1992 2252 lineto
closepath 3 1992 2252 2089 2612 Dp
1702 MX
 1702 2252 lineto
 1799 2252 lineto
 1799 2612 lineto
 1702 2612 lineto
 1702 2252 lineto
closepath 3 1702 2252 1799 2612 Dp
1411 2294 MXY
 1411 2294 lineto
 1508 2294 lineto
 1508 2612 lineto
 1411 2612 lineto
 1411 2294 lineto
closepath 3 1411 2294 1508 2612 Dp
-1 Ds
2158 2238 MXY
 2158 2238 lineto
 2255 2238 lineto
 2255 2252 lineto
 2158 2252 lineto
 2158 2238 lineto
closepath 21 2158 2238 2255 2252 Dp
1868 MX
 1868 2238 lineto
 1965 2238 lineto
 1965 2280 lineto
 1868 2280 lineto
 1868 2238 lineto
closepath 21 1868 2238 1965 2280 Dp
1577 MX
 1577 2238 lineto
 1674 2238 lineto
 1674 2308 lineto
 1577 2308 lineto
 1577 2238 lineto
closepath 21 1577 2238 1674 2308 Dp
1287 2308 MXY
 1287 2308 lineto
 1287 2280 lineto
 1384 2280 lineto
 1384 2308 lineto
 1287 2308 lineto
closepath 21 1287 2280 1384 2308 Dp
2158 2280 MXY
 2158 2280 lineto
 2158 2252 lineto
 2255 2252 lineto
 2255 2280 lineto
 2158 2280 lineto
closepath 14 2158 2252 2255 2280 Dp
1868 2308 MXY
 1868 2308 lineto
 1868 2280 lineto
 1965 2280 lineto
 1965 2308 lineto
 1868 2308 lineto
closepath 14 1868 2280 1965 2308 Dp
1577 2335 MXY
 1577 2335 lineto
 1577 2308 lineto
 1674 2308 lineto
 1674 2335 lineto
 1577 2335 lineto
closepath 14 1577 2308 1674 2335 Dp
1287 2363 MXY
 1287 2363 lineto
 1287 2308 lineto
 1384 2308 lineto
 1384 2363 lineto
 1287 2363 lineto
closepath 14 1287 2308 1384 2363 Dp
2158 2280 MXY
 2158 2280 lineto
 2255 2280 lineto
 2255 2612 lineto
 2158 2612 lineto
 2158 2280 lineto
closepath 3 2158 2280 2255 2612 Dp
1868 2308 MXY
 1868 2308 lineto
 1965 2308 lineto
 1965 2612 lineto
 1868 2612 lineto
 1868 2308 lineto
closepath 3 1868 2308 1965 2612 Dp
1577 2335 MXY
 1577 2335 lineto
 1674 2335 lineto
 1674 2612 lineto
 1577 2612 lineto
 1577 2335 lineto
closepath 3 1577 2335 1674 2612 Dp
1287 2363 MXY
 1287 2363 lineto
 1384 2363 lineto
 1384 2612 lineto
 1287 2612 lineto
 1287 2363 lineto
closepath 3 1287 2363 1384 2612 Dp
4 Ds
1121 2066 MXY
 1121 2066 lineto
 1218 2066 lineto
 1224 2080 lineto
 1127 2080 lineto
 1121 2066 lineto
closepath 21 1121 2066 1224 2080 Dp
2080 MY
 1121 2080 lineto
 1218 2080 lineto
 1218 2273 lineto
 1121 2273 lineto
 1121 2080 lineto
closepath 14 1121 2080 1218 2273 Dp
2273 MY
 1121 2273 lineto
 1218 2273 lineto
 1218 2612 lineto
 1121 2612 lineto
 1121 2273 lineto
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-1 Ds
997 1589 MXY
 997 1589 lineto
 1093 1589 lineto
 1093 1644 lineto
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closepath 21 997 1589 1093 1644 Dp
1644 MY
 997 1644 lineto
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2280 MY
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10 s
719 2093(s)N
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716 1872(c)N
716 1816(e)N
712 1761(S)N
804 2286(10)N
804 1899(20)N
804 1540(30)N
3 Dt
900 1506 MXY
0 1106 Dl
1548 0 Dl
7 s
1978 2828(Elapsed)N
1701 2925(Dynamically)N
2018(grown)X
2184(table)X
2317(\(right\))X
3 Dt
-1 Ds
8 s
720 3180(Figure)N
934(6:)X
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1020(The)X
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892 3910(Since)N
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2271(result-)X
720 4966(ing)N
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2 f
8 s
1269 4941(7)N
1 f
16 s
720 5353 MXY
864 0 Dl
2 f
8 s
760 5408(7)N
1 f
9 s
826 5433(Some)N
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2180(allocator.)X
10 s
2830 1975 MXY
0 -28 Dl
28 0 Dl
0 28 Dl
-28 0 Dl
2853 2004 MXY
0 -27 Dl
28 0 Dl
0 27 Dl
-28 0 Dl
2876 2016 MXY
0 -27 Dl
27 0 Dl
0 27 Dl
-27 0 Dl
2922 1998 MXY
0 -27 Dl
27 0 Dl
0 27 Dl
-27 0 Dl
2967 2025 MXY
0 -28 Dl
28 0 Dl
0 28 Dl
-28 0 Dl
3013 2031 MXY
0 -28 Dl
28 0 Dl
0 28 Dl
-28 0 Dl
3059 MX
0 -28 Dl
27 0 Dl
0 28 Dl
-27 0 Dl
3196 2052 MXY
0 -28 Dl
27 0 Dl
0 28 Dl
-27 0 Dl
3561 2102 MXY
0 -28 Dl
28 0 Dl
0 28 Dl
-28 0 Dl
4292 2105 MXY
0 -28 Dl
27 0 Dl
0 28 Dl
-27 0 Dl
4 Ds
1 Dt
2844 1961 MXY
23 30 Dl
23 12 Dl
45 -18 Dl
46 26 Dl
46 6 Dl
45 0 Dl
137 21 Dl
366 50 Dl
730 3 Dl
9 s
4227 2158(User)N
-1 Ds
3 Dt
2830 1211 MXY
27 Dc
2853 1261 MXY
27 Dc
2876 1267 MXY
27 Dc
2921 1341 MXY
27 Dc
2967 1385 MXY
27 Dc
3013 1450 MXY
27 Dc
3059 1497 MXY
27 Dc
3196 1686 MXY
27 Dc
3561 2109 MXY
27 Dc
4292 2295 MXY
27 Dc
20 Ds
1 Dt
2844 1211 MXY
23 50 Dl
23 6 Dl
45 74 Dl
46 44 Dl
46 65 Dl
45 47 Dl
137 189 Dl
366 423 Dl
730 186 Dl
4181 2270(System)N
-1 Ds
3 Dt
2844 583 MXY
0 28 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
2867 672 MXY
0 27 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
2890 701 MXY
0 28 Dl
0 -14 Dl
13 0 Dl
-27 0 Dl
2935 819 MXY
0 28 Dl
0 -14 Dl
14 0 Dl
-27 0 Dl
2981 849 MXY
0 28 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
3027 908 MXY
0 27 Dl
0 -13 Dl
14 0 Dl
-28 0 Dl
3072 1026 MXY
0 27 Dl
0 -13 Dl
14 0 Dl
-27 0 Dl
3209 1292 MXY
0 27 Dl
0 -14 Dl
14 0 Dl
-27 0 Dl
3575 1823 MXY
0 28 Dl
0 -14 Dl
14 0 Dl
-28 0 Dl
4305 2059 MXY
0 28 Dl
0 -14 Dl
14 0 Dl
-27 0 Dl
5 Dt
2844 597 MXY
23 88 Dl
23 30 Dl
45 118 Dl
46 30 Dl
46 59 Dl
45 118 Dl
137 265 Dl
366 532 Dl
730 236 Dl
4328 2103(Total)N
2844 2310 MXY
1461 0 Dl
2844 MX
0 -1772 Dl
2310 MY
0 18 Dl
4 Ds
1 Dt
2310 MY
0 -1772 Dl
2826 2416(0)N
-1 Ds
5 Dt
3209 2310 MXY
0 18 Dl
4 Ds
1 Dt
2310 MY
0 -1772 Dl
3155 2416(256)N
-1 Ds
5 Dt
3575 2310 MXY
0 18 Dl
4 Ds
1 Dt
2310 MY
0 -1772 Dl
3521 2416(512)N
-1 Ds
5 Dt
3940 2310 MXY
0 18 Dl
4 Ds
1 Dt
2310 MY
0 -1772 Dl
3886 2416(768)N
-1 Ds
5 Dt
4305 2310 MXY
0 18 Dl
4 Ds
1 Dt
2310 MY
0 -1772 Dl
4233 2416(1024)N
-1 Ds
5 Dt
2844 2310 MXY
-18 0 Dl
4 Ds
1 Dt
2844 MX
1461 0 Dl
2771 2340(0)N
-1 Ds
5 Dt
2844 2014 MXY
-18 0 Dl
2844 1719 MXY
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4 Ds
1 Dt
2844 MX
1461 0 Dl
2735 1749(20)N
-1 Ds
5 Dt
2844 1423 MXY
-18 0 Dl
2844 1128 MXY
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4 Ds
1 Dt
2844 MX
1461 0 Dl
2735 1158(40)N
-1 Ds
5 Dt
2844 833 MXY
-18 0 Dl
2844 538 MXY
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4 Ds
1 Dt
2844 MX
1461 0 Dl
2735 568(60)N
3239 2529(Buffer)N
3445(Pool)X
3595(Size)X
3737(\(in)X
3835(K\))X
2695 1259(S)N
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2701 1645(s)N
3 Dt
-1 Ds
3 f
8 s
2706 2773(Figure)N
2908(7:)X
1 f
2982(User)X
3123(time)X
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3854(to)X
3924(the)X
4022(amount)X
4234(of)X
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2706 2861(pool)N
2852(available,)X
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3750(time)X
3895(and)X
4018(elapsed)X
4240(time)X
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3296(to)X
3366(the)X
3464(size)X
3583(of)X
3656(the)X
3753(buffer)X
3927(pool.)X
4092(Even)X
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3439(few)X
3552(collisions,)X
3832(specifying)X
4116(a)X
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4307(buffer)X
2706 3125(pool)N
2836(dramatically)X
3171(improves)X
3425(performance.)X
10 s
10 f
2706 3301 -0.0930(hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh)AN
3 f
3175 3543(Enhanced)N
3536(Functionality)X
1 f
2878 3675(This)N
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2 f
3739(ndbm)X
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3937(interface.)X
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4026(the)X
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2946(Multiple)X
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3224(hsearch)X
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3516(interface.)X
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10 p
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2186(Berkeley)X
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720 1910(Ozan)N
915(\()X
3 f
942(Oz)X
1 f
1040(\))X
1092(Yigit)X
1281(is)X
1358(currently)X
1672(a)X
1732(software)X
2033(engineer)X
2334(with)X
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1499(Research)X
1861(and)X
2044(Development)X
720 2086(group,)N
948(Computing)X
1328(Services,)X
1641(York)X
1826(University.)X
2224(His)X
2355(for-)X
720 2174(mative)N
967(years)X
1166(were)X
1352(also)X
1510(spent)X
1708(at)X
1795(York,)X
2009(where)X
2234(he)X
2338(held)X
720 2262(system)N
985(programmer)X
1425(and)X
1583(administrator)X
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2382(for)X
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995(mixtures)X
1314(of)X
1420(of)X
1526(UNIX)X
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1031(4.1)X
1151(in)X
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1433(while)X
1631(at)X
1709(the)X
1827(same)X
2012(time)X
2174(obtaining)X
720 2526(a)N
776(degree)X
1011(in)X
1093(Computer)X
1433(Science.)X
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813(his)X
931(copious)X
1205(free)X
1356(time,)X
1543(Oz)X
1662(enjoys)X
1896(working)X
2188(on)X
2293(what-)X
720 2728(ever)N
890(software)X
1197(looks)X
1400(interesting,)X
1788(which)X
2014(often)X
2209(includes)X
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1044(interpreters,)X
1464(preprocessors,)X
1960(and)X
2110(lately,)X
2342(pro-)X
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905(generators)X
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1617(systems.)X
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1266(several)X
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2003(software)X
2301(tools,)X
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1545(text)X
1711(formatter)X
2 f
2056(proff)X
1 f
2257(that)X
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1226(used)X
1397(in)X
1483(some)X
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2173(His)X
2307(latest)X
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1460(the)X
1639(incredible)X
2040(programming)X
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1030(Scheme,)X
1324(and)X
1460(Chinese)X
1738(Brush)X
1949(painting.)X
3 f
720 5960(USENIX)N
9 f
1042(-)X
3 f
1106(Winter)X
1371('91)X
9 f
1498(-)X
3 f
1562(Dallas,)X
1815(TX)X
4384(13)X

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2970(USENIX)X
9 f
3292(-)X
3 f
3356(Winter)X
3621('91)X
9 f
3748(-)X
3 f
3812(Dallas,)X
4065(TX)X

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