c++第三次作业

#include  <iostream>
using namespace std;
int main()
{
int a,money;
cout<<"欢迎使用利息计算器"<<endl;
cout<<"请输入存款金额"<<endl;
cin>>money;
cout<<"=====存款金额期限=====\n""1.三个月\n""2.6个月\n""3.一年\n""4.二年\n""5.三年\n""6.五年"<<endl;
cout<<"请输入存款金额的代号"<<endl;
cin>>a;
double b,c;
switch(a)
{case 1: b=money+money*0.031*0.25; c=money*0.031*0.25;
cout<<"到期利息为:"<<c<<"元"<<"本息合计共"<<b<<"元"<<endl;break;
case 2:  b=money+money*0.033*0.5;  c=money*0.033*0.5;
cout<<"到期利息为:"<<c<<"元"<<"本息合计共"<<b<<"元"<<endl;break;
case 3: b=money+money*0.35*1; c=money*0.35*1;
cout<<"到期利息为:"<<c<<"元"<<"本息合计共"<<b<<"元"<<endl;break;
case 4: b=money*0.044*2+money;  c=money*0.044*2;
cout<<"到期利息为:"<<c<<"元"<<"本息合计共"<<b<<"元"<<endl;break;
case 5: b=money+money*0.05*3;  c=money*0.05*3;
cout<<"到期利息为:"<<c<<"元"<<"本息合计共"<<b<<"元"<<endl;break;
case 6:  b=money+money*0.055*5;  c=money*0.055*5;
cout<<"到期利息为:"<<c<<"元"<<"本息合计共"<<b<<"元"<<endl;break;
default:cout<<"错误\n";break;
}
cout<<"感谢你的使用，欢迎下次光临!";
return 0;
}

#include <iostream>
using namespace std;
int main()
{
int year,month;
cout<<"输入年份，月份"<<endl;
cin>>year>>month;
if(month==1||month==3||month==5||month==7||month==8||month==10||month==12)
cout<<"本月有31天";
else if(month==4||month==6||month==9||month==11)
cout<<"本月有30天";
else if(month==2)
{
if(year%4==0&&year%100!=0||year%400==0)
cout<<"本月有29天";
else
cout<<"本月有28天";
}
return 0;
}

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