c++作业3

<span style="font-size:24px;">一、本月有多少天</span>

#include <iostream>
using namespace std;
int main()
{
int a,b,c;
cout<<"请输入年份:";
cin>>a;
cout<<"请输入月份:";
cin>>b;
switch(b)
{
case 1:case 3:case 5:case 7:case 8:case 10:case 12:
c=31;
break;
case 4:case 6:case 9:case 11:
c=30;
break;
case 2:
if(a%400==0||a%4==0&&a%100!=0)
c=29;
else
c=28;
}
cout<<a<<"年份"<<b<<"月份的天数是:"<<c<<endl;
return 0;
}

#include <iostream>
14.using namespace std;
15.int main( )
16.{
17.    double dSalary,dTax=0,dNetIncome=0,da;
18.    cout<<"请输入您本月的收入总额（元）：";
19.    cin>>dSalary;
20.    da=dSalary-3500;
21.    if(da<0)
22.        cout<<"您不需要缴纳个人所得税\n";
23.    else
24.    {
25.        if(da>0&&dv<=1500)
26.            dTax=da*0.03;
27.        else if(da>1500&&da<=4500)
28.            dTax=da*0.1-105;
29.        else if(da>4500&&da<=9000)
30.            dTax=da*0.2-555;
31.        else if(da>9000&&da<=35000)
32.            dTax=da*0.25-1005;
33.        else if(da>35000&&da<=55000)
34.            dTax=da*0.3-2755;
35.        else if(da>55000&&da<=80000)
36.            dTax=da*0.35-5505;
37.        else if(da>80000)
38.            dTax=da*0.45-13505;
39.    }
40.    dNetIncome=dSalary-dTax;
41.    cout<<"您本月应缴个人所得税 "<<dTax<<" 元，税后收入是 "<<dNetIncome<<" 元。\n";
42.    cout<<"依法纳税，共享繁荣。谢谢使用！\n";
43.    return 0;
44.}

01.#include<iostream>
02.#include<cmath>
03.using namespace std;
04.int main()
05.{
06.    double x,y;
07.    cout<<"请输入x的值（要求为实数）"<<endl;
08.    cin>>x;
09.    if(x<2)
10.        y=x;
11.    else if(x<6)
12.        y=x*x+1;
13.    else if(x<10)
14.        y=sqrt(x+1);
15.    else
16.        y=1/(x+1);
17.    cout<<"y="<<y<<endl;
18.    return 0;
19.}