c++作业3

#include<iostream>
using namespace std;
int main()
{
int y;
char m;
cout<<"请输入年份：";
cin>>y;
cout<<"请输入月份：";
cin>>m;
switch(m)
{
case'1':cout<<"本月31天";break;
case'2':
{if((y%4==0&&y%100!=0)|y%400==0)  cout<<"本月29天";
else     cout<<"本月28天";break;}
case'3':cout<<"本月31天";break;
case'4':cout<<"本月30天";break;
case'5':cout<<"本月31天";break;
case'6':cout<<"本月30天";break;
case'7':cout<<"本月31天";break;
case'8':cout<<"本月31天";break;
case'9':cout<<"本月30天";break;
case'10':cout<<"本月31天";break;
case'11':cout<<"本月30天";break;
case'12':cout<<"本月31天";break;
}
return 0;
}

#include<iostream>
using namespace std;
int main()
{
double a,b,c;
char n;
cout<<"欢迎使用利息计算器，请输入存款金额：";
cin>>a;
cout<<"=====存款期限======\n1、3个月\n2、6个月\n3、一年\n4、两年\n5、三年\n6、五年\n";
cout<<"请输入存款期限的代号：";
cin>>n;
switch(n)
{case'1':b=a*0.031*3/12;break;
case'2':b=a*0.033*6/12;break;
case'3':b=a*0.035;break;
case'4':b=a*0.044*2;break;
case'5':b=a*0.05*3;break;
case'6':b=a*0.055*5;}
c=a+b;
cout<<"到期利息为；"<<b<<"元，本息合计共"<<c<<"元。\n";
cout<<"感谢您的使用，欢迎下次光临！\n";
return 0;
}

#include<iostream>
#include<cmath>
using namespace std;
int main()
{
double y,x;
cout<<"请输入x的值：";
cin>>x;
if(x<2) y=x;
else if(x<6) y=x*x+1;
else if(x<10) y=sqrt(x+1);
else if(x>=10) y=1/(x+1);
cout<<"输出y的值为："<<y;
return 0;
}