4.3BSD - /usr/src/games/arithmetic.c

   1: 
   2: static char sccsid[] = "	arithmetic.c	4.1	82/10/24	";
   3: 
   4: #include <stdio.h>
   5: #include <signal.h>
   6: #define MAX 100
   7: 
   8: char    types[10];
   9: int right[MAX];
  10: int left[MAX];
  11: int rights;
  12: int wrongs;
  13: long    stvec;
  14: long    etvec;
  15: long    dtvec;
  16: 
  17: main(argc,argv)
  18: char    *argv[];
  19: {
  20:     int range, k, dif, l;
  21:     char line[100];
  22:     int ans,pans,i,j,t;
  23:     char    dir,sense;
  24:     extern  delete();
  25: 
  26:     signal(SIGINT, delete);
  27: 
  28:     range = 11;
  29:     dif = 0;
  30:     while(argc > 1) {
  31:         switch(*argv[1]) {
  32:         case '+':
  33:         case '-':
  34:         case 'x':
  35:         case '/':
  36:             while(types[dif] = argv[1][dif])
  37:                 dif++;
  38:             break;
  39: 
  40:         default:
  41:             range = getnum(argv[1]) + 1;
  42:         }
  43:         argv++;
  44:         argc--;
  45:     }
  46:     if(range > MAX) {
  47:         printf("Range is too large.\n");
  48:         exit();
  49:     }
  50: 
  51:     if(dif == 0) {
  52:         types[0] = '+';
  53:         types[1] = '-';
  54:         dif = 2;
  55:     }
  56: 
  57:     for(i = 0; i < range; i++) {
  58:         left[i] = right[i] = i;
  59:     }
  60:     time(&stvec);
  61:     k = stvec;
  62:     srand(k);
  63:     k = 0;
  64:     l = 0;
  65:     goto start;
  66: 
  67: loop:
  68:     if(++k%20 == 0)
  69:         score();
  70: 
  71: start:
  72:     i = skrand(range);
  73:     j = skrand(range);
  74:     if(dif > 1)
  75:         l = random(dif);
  76: 
  77:     switch(types[l]) {
  78:         case '+':
  79:         default:
  80:             ans = left[i] + right[j];
  81:             printf("%d + %d =   ", left[i], right[j]);
  82:             break;
  83: 
  84:         case '-':
  85:             t = left[i] + right[j];
  86:             ans = left[i];
  87:             printf("%d - %d =   ", t, right[j]);
  88:             break;
  89: 
  90:         case 'x':
  91:             ans = left[i] * right[j];
  92:             printf("%d x %d =   ", left[i], right[j]);
  93:             break;
  94: 
  95:         case '/':
  96:             while(right[j] == 0)
  97:                 j = random(range);
  98:             t = left[i] * right[j] + random(right[j]);
  99:             ans = left[i];
 100:             printf("%d / %d =   ", t, right[j]);
 101:             break;
 102:     }
 103: 
 104: 
 105: loop1:
 106:     getline(line);
 107:     dtvec += etvec - stvec;
 108:     if(line[0]=='\n') goto loop1;
 109:     pans = getnum(line);
 110:     if(pans == ans) {
 111:         printf("Right!\n");
 112:         rights++;
 113:         goto loop;
 114:     }
 115:     else {
 116:         printf("What?\n");
 117:         wrongs++;
 118:         if(range >= MAX)    goto loop1;
 119:         left[range] = left[i];
 120:         right[range++] = right[j];
 121:         goto loop1;
 122:     }
 123: }
 124: 
 125: getline(s)
 126: char *s;
 127: {
 128:     register char   *rs;
 129: 
 130:     rs = s;
 131: 
 132:     while((*rs = getchar()) == ' ');
 133:     while(*rs != '\n')
 134:         if(*rs == 0)
 135:             exit();
 136:         else if(rs >= &s[99]) {
 137:             while((*rs = getchar()) != '\n')
 138:                 if(*rs == '\0') exit();
 139:         }
 140:         else
 141:             *++rs = getchar();
 142:     while(*--rs == ' ')
 143:         *rs = '\n';
 144: }
 145: 
 146: getnum(s)
 147: char *s;
 148: {
 149:     int a;
 150:     char    c;
 151: 
 152:     a = 0;
 153:     while((c = *s++) >= '0' && c <= '9') {
 154:         a = a*10 + c - '0';
 155:     }
 156:     return(a);
 157: }
 158: 
 159: int arand;
 160: 
 161: srand(n)
 162: {
 163:     arand = n&077774 | 01;
 164: }
 165: 
 166: rand()      /*uniform on 0 to 2**13-1*/
 167: {
 168: 
 169:     arand *= 3125;
 170:     arand &= 077777;
 171:     return(arand/4);
 172: }
 173: 
 174: random(range)
 175: {
 176:     return(hmul(rand(), 8*range));
 177: }
 178: 
 179: skrand(range){
 180: int temp;
 181:     temp = rand() + rand();
 182:     if(temp >017777) temp = 040000 - temp;
 183:     return(hmul(temp,8*range));
 184:     }
 185: 
 186: /* 'hmul' returns the upper 16 bits of the product, where the operands
 187:    are assumed to be 16-bit integers. It replaces an old PDP-11
 188:    assembler language subroutine. -- dks.
 189: */
 190: hmul(a,b) { return(a*b >> 16); }
 191: score()
 192: {
 193:     time(&etvec);
 194: 
 195:     printf("\n\nRights %d; Wrongs %d; Score %d%%\n", rights, wrongs,
 196:         (rights * 100)/(rights + wrongs));
 197: 
 198:     if(rights == 0) return;
 199:     printf("Total time %ld seconds; %.1f seconds per problem\n\n\n",
 200:         etvec - stvec,
 201:         (etvec - stvec) / (rights + 0.));
 202: 
 203:     sleep(3);
 204:     time(&dtvec);
 205:     stvec += dtvec - etvec;
 206:     return(0);
 207: }
 208: 
 209: delete()
 210: {
 211:     if(rights + wrongs == 0.) {
 212:         printf("\n");
 213:         exit();
 214:     }
 215:     score();
 216:     exit();
 217: }

Defined functions

Defined variables

Defined macros