练习，计算个人所得税

#include<iostream>#include<cmath>using namespace std;int main(){    double a,dSalary,dTax,dNetIncome;    cout<<"输入工资总额：";    cin>>dSalary;    a=dSalary-3500;    if(a<0)        cout<<"不需扣税，工资为："<<dSalary<<endl;    else    {        if(a<=1500)            dTax=a*0.03;        else if(a<=4500)            dTax=a*0.10-105;        else if(a<=9000)            dTax=a*0.20-555;        else if(a<35000)            dTax=a*0.25-1005;        else if(a<55000)            dTax=a*0.30-2755;        else if(a<80000)            dTax=a*0.35-5505;        else            dTax=a*0.45-13505;    dNetIncome=dSalary-dTax;    cout<<"应缴纳税款为："<<dTax<<"元 。"<<endl;    cout<<"税后工资为："<<dNetIncome<<"元 。\n";    }    return 0;}