generator.c

   1 /* Simple generator of text files for the genetic program testing. */
   2
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5
   6 int
   7 main(int argc, char *argv[])
   8 {
   9         /* Test if we were executed properly. */
  10         if (argc != 4) {
  11                 fprintf(stderr, "Usage: %s EQUATION_COUNT INPUT_FILE OUTPUT_FILE\n", argv[0]);
  12                 exit(EXIT_FAILURE);
  13         }
  14
  15         /* Retrieve parameters. */
  16         int eqcount = atoi(argv[1]);
  17         FILE *infile = fopen(argv[2], "w");
  18         if (!infile) {
  19                 perror(argv[2]);
  20                 exit(EXIT_FAILURE);
  21         }
  22         FILE *outfile = fopen(argv[3], "w");
  23         if (!outfile) {
  24                 perror(argv[2]);
  25                 exit(EXIT_FAILURE);
  26         }
  27
  28         /* Produce equations. */
  29         for (int i = 0; i < eqcount; i++) {
  30                 /* Available operators. */
  31                 static char ops[4] = "+-*/";
  32
  33                 /* Pick an operator and parameters. */
  34                 int arg1 = rand() % 100; /* 0 to 99 */
  35                 char op = ops[rand() % 4]; /* random operator character */
  36                 int arg2 = rand() % 100; /* 0 to 99 */
  37
  38                 /* Make sure we do not divide by zero. */
  39                 if (op == '/' && arg2 == 0)
  40                         arg2 = 1 + rand() % 99; /* 1 to 99 */
  41
  42                 /* Write the equation. */
  43                 fprintf(infile, "%d%c%d=\n", arg1, op, arg2);
  44
  45                 /* Figure out the result. */
  46                 int result = 0;
  47                 switch (op) {
  48                         case '+': result = arg1 + arg2; break;
  49                         case '-': result = arg1 - arg2; break;
  50                         case '*': result = arg1 * arg2; break;
  51                         case '/': result = arg1 / arg2; break;
  52                 }
  53
  54                 /* Write the result. */
  55                 fprintf(outfile, "%d\n", result);
  56         }
  57 }