这个的实验报告怎么写？😭

计算个人工资所得税金M。
超额累进税制，免征额5000元，税率r(工资额为x，单位:元):
x≤5000， r=0;
5000<x≤8000,r=0.03;
8000<x≤17000,r=0.10:
17000<x≤30000,r=0.20;
30000<x, r=0.25。

回答：开始缴税咯，代码如下：

#include <stdio.h>

int main()
{
    float M;
    int freeTax = 5000;
    int firstTax = 8000;
    int secondTax = 17000;
    int thirdTax = 30000;
    float r;
    int x;
    
    scanf("%d", &x);

    if (x <= freeTax)
    {
        M = 0;
    }
    else if (x > freeTax && x <= firstTax)
    {
        r = 0.03;
        M = (x - freeTax) * r;
    }
    else if (x > firstTax && x <= secondTax)
    {
        r = 0.10;
        M = (x - firstTax) * r + (firstTax - freeTax) * 0.03;
    }
    else if (x > secondTax && x <= thirdTax)
    {
        r = 0.20;
        M = (x - secondTax) * r + (secondTax - firstTax) * 0.10 + (firstTax - freeTax) * 0.03;
    }
    else
    {
        r = 0.25;
        M = (x - thirdTax) * r + (thirdTax - secondTax) * 0.20 + (secondTax - firstTax) * 0.10 + (firstTax - freeTax) * 0.03;
    }
    
    printf("Tax = %f\n", M);

    return 0;
}

/*
测试数据：
5000

8000

17000

30000

20000
*/