#include

int main()

{

int a,b;

char c;

printf("輸入運算公式（形如 1+2 ）");

scanf("%d%c%d",&a,&c,&b);

switch(c)

{

case "+":printf("%d+%d=%d\n",a,b,a+b);

break;

case "-":printf("%d-%d=%d\n",a,b,a-b);

break;

case "*":printf("%d*%d=%d\n",a,b,a*b);

break;

case "/":

{

if ( b == 0 )

{

printf("被除數為0，非法！\n");

}

else

{

printf("%d/%d=%d\n",a,b,a/(1.0*b) );

}

}

break;

default:

printf("輸入的運算子非法！\n");

break;

}

return 0;

}