个人所得税
#include <stdio.h>
int main(void)
{
double income, tax;
printf("Input income:");
scanf("%lf", &income);
/*************** Begin ***************/
if(income<=800)
tax=0;
else if(income<=4000)
tax=(income-800)*0.2;
else if(income<=20000)
tax=(income-income*0.2)*0.2;
else if(income<=50000)
tax=(income-income*0.2)*0.3+1200;
else
tax=(income-income*0.2)*0.4+1800;

/*************** End ***************/
printf("fee = %.0f\n", tax);
return 0;
}