projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| aedb329b | 1 | #ifndef lint |
| 0f4556f1 | 2 | static char sccsid[] = "@(#)selunit.c 4.2 (Berkeley) 4/25/83"; |
| aedb329b KM |
3 | #endif not lint |
| 4 | ||
| 5 | #include "stdio.h" | |
| 6 | #include "lrnref.h" | |
| 7 | ||
| 8 | int nsave = 0; | |
| 2b9e3de9 | 9 | int review = 0; |
| aedb329b KM |
10 | |
| 11 | selunit() | |
| 12 | { | |
| aedb329b | 13 | static char dobuff[50]; |
| 2b9e3de9 KM |
14 | static char saved[20]; |
| 15 | char fnam[80], s[80], zb[200]; | |
| aedb329b KM |
16 | char posslev[20][20]; |
| 17 | int diff[20], i, k, m, n, best, alts; | |
| 2b9e3de9 | 18 | char *getlesson(); |
| aedb329b | 19 | FILE *f; |
| aedb329b | 20 | |
| 2b9e3de9 KM |
21 | if (again) { |
| 22 | again = 0; | |
| 23 | if (todo=getlesson()) { | |
| 24 | if (!review) | |
| 25 | unsetdid(todo); | |
| 26 | return; | |
| 27 | } | |
| 28 | wrapup(1); | |
| 29 | } | |
| aedb329b KM |
30 | while (ask) { |
| 31 | printf("What lesson? "); | |
| 32 | fflush(stdout); | |
| 33 | gets(dobuff); | |
| 34 | if (strcmp(dobuff, "bye") == 0) | |
| 2b9e3de9 KM |
35 | wrapup(1); |
| 36 | level = dobuff; | |
| 37 | if (todo=getlesson()) | |
| aedb329b | 38 | return; |
| aedb329b KM |
39 | } |
| 40 | alts = 0; | |
| 41 | retry: | |
| 2b9e3de9 | 42 | f = scrin; /* use old lesson to find next */ |
| aedb329b | 43 | if (f==NULL) { |
| 2b9e3de9 | 44 | sprintf(fnam, "%s/%s/L%s", direct, sname, level); |
| aedb329b KM |
45 | f = fopen(fnam, "r"); |
| 46 | if (f==NULL) { | |
| 2b9e3de9 KM |
47 | perror(fnam); |
| 48 | fprintf(stderr, "Selunit: no script for lesson %s.\n", level); | |
| aedb329b KM |
49 | wrapup(1); |
| 50 | } | |
| 51 | while (fgets(zb, 200, f)) { | |
| 52 | trim(zb); | |
| 53 | if (strcmp(zb, "#next")==0) | |
| 54 | break; | |
| 55 | } | |
| 56 | } | |
| 57 | if (feof(f)) { | |
| 58 | printf("Congratulations; you have finished this sequence.\n"); | |
| 59 | fflush(stdout); | |
| 60 | todo = 0; | |
| 61 | return; | |
| 62 | } | |
| 2b9e3de9 | 63 | for(i=0; fgets(s, 80, f); i++) { |
| aedb329b KM |
64 | sscanf(s, "%s %d", posslev[i], &diff[i]); |
| 65 | } | |
| 66 | best = -1; | |
| 67 | /* cycle through lessons from random start */ | |
| 68 | /* first try the current place, failing that back up to | |
| 69 | last place there are untried alternatives (but only one backup) */ | |
| 70 | n = grand()%i; | |
| 71 | for(k=0; k<i; k++) { | |
| 72 | m = (n+k)%i; | |
| 2b9e3de9 KM |
73 | if (already(posslev[m])) |
| 74 | continue; | |
| 75 | if (best<0) | |
| 76 | best = m; | |
| 77 | alts++; /* real alternatives */ | |
| aedb329b | 78 | if (abs(diff[m]-speed) < abs(diff[best]-speed)) |
| 2b9e3de9 | 79 | best = m; |
| aedb329b KM |
80 | } |
| 81 | if (best < 0 && nsave) { | |
| 82 | nsave--; | |
| 83 | strcpy(level, saved); | |
| 84 | goto retry; | |
| 85 | } | |
| 2b9e3de9 | 86 | if (best < 0) { |
| aedb329b KM |
87 | /* lessons exhausted or missing */ |
| 88 | printf("Sorry, there are no alternative lessons at this stage.\n"); | |
| 89 | printf("See someone for help.\n"); | |
| 90 | fflush(stdout); | |
| 91 | todo = 0; | |
| 92 | return; | |
| 93 | } | |
| 94 | strcpy (dobuff, posslev[best]); | |
| 95 | if (alts>1) { | |
| 2b9e3de9 KM |
96 | nsave = 1; |
| 97 | strcpy(saved, level); | |
| aedb329b KM |
98 | } |
| 99 | todo = dobuff; | |
| 100 | fclose(f); | |
| 101 | } | |
| 102 | ||
| 103 | abs(x) | |
| 104 | { | |
| 2b9e3de9 | 105 | return(x>=0 ? x : -x); |
| aedb329b KM |
106 | } |
| 107 | ||
| 108 | grand() | |
| 109 | { | |
| 110 | static int garbage; | |
| 111 | int a[2], b; | |
| 112 | ||
| 113 | time(a); | |
| 114 | b = a[1]+10*garbage++; | |
| 115 | return(b&077777); | |
| 116 | } |