C语言编程计算超额累进制奖金的方法

#include "stdafx.h"
#include "stdio.h"
int main()
{
long i;
float bonus,bon1,bon2,bon4,bon6,bon10;
int branch;
bon1=100000*0.1;
bon2=bon1+100000*0.075;
bon4=bon2+200000*0.05;
bon6=bon4+200000*0.03;
bon10=bon6+400000*0.015;
printf("请输入利润:");
scanf("%ld",&i);
branch=i/100000;
if(branch>10)
branch=10;
switch(branch)
{
case 0: bonus=i*0.1;break;
case 1:bonus=bon1+(i-100000)*0.075;break;
case 2:
case 3:bonus=bon2+(i-200000)*0.05;break;
case 4:
case 5:bonus=bon4+(i-400000)*0.03;break;
case 6:
case 7:
case 8:
case 9:bonus=bon6+(i-600000)*0.015;break;
case 10:bonus=bon10+(i-1000000)*0.01;
}
printf("奖金是%10.2f\n",bonus);
return 0;
}

-_-!

真是令人费解！