※以下のソースコードはコピー防止の対応をしています．
01: #include <stdio.h>
02:
03: int main(void)
04: {
05: int a, b, op;
06:
07: printf("a=");
08: scanf("%d", &a);
09: printf("op(0:plus, 1:minus, 2:multiply): ");
10: scanf("%d", &op);
11: printf("b=");
12: scanf("%d", &b);
13:
14: if(op == 0)
15: {
16: printf("%d + %d = %d\n", a, b, a+b);
17: }
18: else if(op == 1)
19: {
20: printf("%d - %d = %d\n", a, b, a-b);
21: }
22: else if(op == 2)
23: {
24: printf("%d * %d = %d\n", a, b, a*b);
25: }
26: else
27: {
28: printf("undefined\n");
29: }
30: return 0;
31: }