用三目运算符
#include <stdio.h>
int main()
{
int a,b;
char c;
scanf("%d%c%d",&a,&c,&b);
c=='+'?printf("%d",a+b):c=='-'?printf("%d",a-b):printf("error!");
return 0;
}
供参考:
#include <stdio.h>
int main()
{
char s[64],op[2];
int a,b;
gets(s);
sscanf(s,"%d %[^0-9 ] %d",&a,op,&b);
op[0] == '+' ? printf("%d",a+b) : (op[0] == '-' ? printf("%d",a-b) : printf("error!"));
return 0;
}