C语言问题
代码如下:
#include <stdio.h>
#define RATE1 0.15;
#define RATE2 0.28;
int main()
{
double tax,limit,m;
int num;
printf("Select the type of marriage:\n");
printf("1)SINGLE\t2)HOST\t3)MARRIED_SHARE\n4)MARRIED_DIVORCE\t5)quit\n");
while(scanf("%d",&num)==1 )
switch(num)
{
case 1:limit=17850.0;break;
case 2:limit=23900.0;break;
case 3:limit=29750.0;break;
case 4:limit=14875.0;break;
case 5:printf("Done!\n");
return 0;
default :printf("Please enter a valid figure:\n");
return num;
}
printf("Please enter your income:\n");
scanf("%.2lf",&m);
printf("you have select %d\n",num);
printf("input the pay:");
scanf("%lf",&m);
if (m <= limit)
tax = m * RATE1;
else
tax = limit * RATE1 + (m - limit) * RATE2;
printf("tax is %.2lf\n",tax);
return 0;
}
请问为何会操作无效。