作业：C++作业3

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

#include <iostream>
using namespace std;
int main( )
{
int money,time;double accrual,captial=0;
cout<<"欢迎使用利息计算器！\n""请输入存款金额:";
cin>>money;
cout<<"======存款期限======\n";
cout<<"1. 3个月\n"<<"2. 6个月\n"<<"3. 一年\n"<<"4. 二年\n"<<"5. 三年\n"<<"6. 五年\n";
cout<<"请输入存款期限的代号：";
cin>>time;
switch(time)
{case 1:accrual=money*0.0310*0.25;cout<<accrual;break;
case 2:accrual=money*0.0330*0.5;cout<<accrual;break;
case 3:accrual=money*0.0350*1;cout<<accrual;break;
case 4:accrual=money*0.0440*2;cout<<accrual;break;
case 5:accrual=money*0.0500*3;cout<<accrual;break;
case 6:accrual=money*0.0550*5;cout<<accrual;break;
}
captial=money+accrual;
cout<<"到期利息为:"<<accrual<<endl;
cout<<"本息合计共:"<<captial<<endl;
return 0;
}

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