真分数四则

#include<stdio.h>
  #include<Windows.h>
  #include<time.h>
  void main()
  {
      int a, b, c, d,i,e,n;
      float p, q;
      srand(unsigned( time(NULL)));
      for (i = 0; i < 30; i++)
      {
          a = rand() % 100;
             b = rand() % 100;
             e = rand() % 100;
             n = rand() % 100;
             c = rand() %4 ;
             while (b == 0)
             {
                 b = rand() % 100;
             }
             while (n == 0)
             {
                 n = rand() % 100;
             }
             if (a>b)
             {
                 d=a;
                 a=d;
                 d=b;
             }
             if (c>d)
             {
                 d=c;
                 c=d;
                 d=b;
             }
             switch (c)
             {
             case 0:printf("%d/%d + %d/%d =\n", a, b, e, n);
                 break;
             case 1:
                 p = a / b;
                 q = e / n;
                 if (p < q)
                 {
                    d = a;
                     a = e;
                     e = d;
                     d = b;
                     b = n;
                     n = d;
                 }
                 printf("%d/%d - %d/%d =\n", a,b,e,n);
                 break;
             case 2:printf("%d/%d * %d/%d =\n", a, b, e, n);
                 break;
             case 3:
                 a = rand() % 100;
                 b = rand() % 100;
                 e = rand() % 100;
                 n = rand() % 100;
                 c = rand() % 4;
                 while (e == 0)
                 {
                     e = rand() % 100;
                }
                 printf("%d/%d / %d/%d =\n", a, b, e, n);
                 break;
             }
  
      }
     system("pause");
 }