projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 26b5ab8e KB |
1 | /* |
| 2 | * Copyright (c) 1989 The Regents of the University of California. | |
| 3 | * All rights reserved. | |
| 4 | * | |
| 5 | * This code is derived from software contributed to Berkeley by | |
| 6 | * Robert Paul Corbett. | |
| 7 | * | |
| 8 | * Redistribution and use in source and binary forms are permitted | |
| 9 | * provided that the above copyright notice and this paragraph are | |
| 10 | * duplicated in all such forms and that any documentation, | |
| 11 | * advertising materials, and other materials related to such | |
| 12 | * distribution and use acknowledge that the software was developed | |
| 13 | * by the University of California, Berkeley. The name of the | |
| 14 | * University may not be used to endorse or promote products derived | |
| 15 | * from this software without specific prior written permission. | |
| 16 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR | |
| 17 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED | |
| 18 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. | |
| 19 | */ | |
| 20 | ||
| 21 | #ifndef lint | |
| 22 | static char sccsid[] = "@(#)warshall.c 5.1 (Berkeley) %G%"; | |
| 23 | #endif /* not lint */ | |
| 24 | ||
| 25 | #include "defs.h" | |
| 26 | ||
| 27 | transitive_closure(R, n) | |
| 28 | unsigned *R; | |
| 29 | int n; | |
| 30 | { | |
| 31 | register int rowsize; | |
| 32 | register unsigned mask; | |
| 33 | register unsigned *rowj; | |
| 34 | register unsigned *rp; | |
| 35 | register unsigned *rend; | |
| 36 | register unsigned *ccol; | |
| 37 | ||
| 38 | unsigned *relend; | |
| 39 | unsigned *cword; | |
| 40 | unsigned *rowi; | |
| 41 | ||
| 42 | rowsize = ROWSIZE(n); | |
| 43 | relend = (unsigned *) ((unsigned) R + n*rowsize); | |
| 44 | ||
| 45 | cword = R; | |
| 46 | mask = 1; | |
| 47 | rowi = R; | |
| 48 | while (rowi < relend) | |
| 49 | { | |
| 50 | ccol = cword; | |
| 51 | rowj = R; | |
| 52 | ||
| 53 | while (rowj < relend) | |
| 54 | { | |
| 55 | if (*ccol & mask) | |
| 56 | { | |
| 57 | rp = rowi; | |
| 58 | rend = (unsigned *) ((unsigned) rowj + rowsize); | |
| 59 | ||
| 60 | while (rowj < rend) | |
| 61 | *rowj++ |= *rp++; | |
| 62 | } | |
| 63 | else | |
| 64 | { | |
| 65 | rowj = (unsigned *) ((unsigned) rowj + rowsize); | |
| 66 | } | |
| 67 | ||
| 68 | ccol = (unsigned *) ((unsigned) ccol + rowsize); | |
| 69 | } | |
| 70 | ||
| 71 | mask <<= 1; | |
| 72 | if (mask == 0) | |
| 73 | { | |
| 74 | mask = 1; | |
| 75 | cword++; | |
| 76 | } | |
| 77 | ||
| 78 | rowi = (unsigned *) ((unsigned) rowi + rowsize); | |
| 79 | } | |
| 80 | } | |
| 81 | ||
| 82 | reflexive_transitive_closure(R, n) | |
| 83 | unsigned *R; | |
| 84 | int n; | |
| 85 | { | |
| 86 | register int rowsize; | |
| 87 | register unsigned mask; | |
| 88 | register unsigned *rp; | |
| 89 | register unsigned *relend; | |
| 90 | ||
| 91 | transitive_closure(R, n); | |
| 92 | ||
| 93 | rowsize = ROWSIZE(n); | |
| 94 | relend = (unsigned *) ((unsigned) R + n*rowsize); | |
| 95 | ||
| 96 | mask = 1; | |
| 97 | rp = R; | |
| 98 | while (rp < relend) | |
| 99 | { | |
| 100 | *rp |= mask; | |
| 101 | ||
| 102 | mask <<= 1; | |
| 103 | if (mask == 0) | |
| 104 | { | |
| 105 | mask = 1; | |
| 106 | rp++; | |
| 107 | } | |
| 108 | ||
| 109 | rp = (unsigned *) ((unsigned) rp + rowsize); | |
| 110 | } | |
| 111 | } |