c语言---简易计算器

#include<stdio.h>

int main(void)
{
double number1 = 0.0;
double number2 = 0.0;
char operation = 0;

printf("\n Enter the calculation!! \n");
scanf("%lf%c%lf", &number1,&operation,&number2);

switch(operation)
{
case '+':
printf(" =%lf\n", number1+number2);
break;
case '-':
printf(" =%lf\n", number1-number2);
break;
case '*':
printf(" =%lf\n", number1*number2);
break;
case '/':
if(!number2){
printf(" wrong !!!  ");}

printf(" =%lf\n", number1/number2);
break;
case '%':
if(!number2)
printf(" wrong !!!");
printf(" =%ld\n",(long) number1%(long)number2);
break;
defult :
printf("Wrong !!!");
break;

}
}