四则运算

 1 #include <stdio.h>
 2 #include <stdlib.h>
 3 #include <time.h>
 4 #include <math.h>
 5 
 6 int main()
 7 {
 8     int i = 0;
 9     int n = 0;
10     int x = 0;
11     int type;
12     char flag;
13     int left, right;
14     float result1,result2;
15     printf("请输入要出的题目数量\n");
16     scanf_s("%d", &n);
17     srand(unsigned(time(NULL)));
18     while (x<n)
19     {
20         type = rand() % 4;
21         left = rand() % 100;
22         right = rand() % 100;
23         switch (type)
24         {
25         case 0:
26             printf("%d + %d = ?\n", left, right);
27             result1 = left + right;
28             break;
29         case 1:
30             printf("%d - %d = ?\n", left, right);
31             result1 = left -right;
32             break;
33         case 2:
34             printf("%d * %d = ?\n", left, right);
35             result1 = left * right;
36             break;
37         case 3:
38             printf("%d / %d = ?\n", left, right);
39             result1 = (float)left / right;
40             break;
41         }
42         printf_s("请输入答案：");
43         scanf_s("%f",&result2);
44         if (fabs(result1 - result2)<=1e-6)
45         {
46             printf_s("计算正确\n");
47         }
48         else
49         {
50             printf_s("计算错误\n");
51         }
52 
53 
54         i++;
55         while (i >= n)
56         {
57             
58             printf("谢谢使用！\n");
59             fflush(stdin);
60             getchar();
61             return 0;
62         }
63     }
64 }