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(year%4==0&&year%100!=0||year%400==0)

switch(month)
{    case 1:cout<<"本月有31天\n";break;
case 2:cout<<"本月有29天\n";break;
case 3:cout<<"本月有31天\n";break;
case 4:cout<<"本月有30天\n";break;
case 5:cout<<"本月有31天\n";break;
case 6:cout<<"本月有30天\n";break;
case 7:cout<<"本月有31天\n";break;
case 8:cout<<"本月有31天\n";break;
case 9:cout<<"本月有30天\n";break;
case 10:cout<<"本月有31天\n";break;
case 11:cout<<"本月有30天\n";break;
case 12:cout<<"本月有31天\n";break;
default:cout<<"error\n";break;}
else
switch(month)
{    case 1:cout<<"本月有31天\n";break;
case 2:cout<<"本月有28天\n";break;
case 3:cout<<"本月有31天\n";break;
case 4:cout<<"本月有30天\n";break;
case 5:cout<<"本月有31天\n";break;
case 6:cout<<"本月有30天\n";break;
case 7:cout<<"本月有31天\n";break;
case 8:cout<<"本月有31天\n";break;
case 9:cout<<"本月有30天\n";break;
case 10:cout<<"本月有31天\n";break;
case 11:cout<<"本月有30天\n";break;
case 12:cout<<"本月有31天\n";break;
default:cout<<"error\n";break;}
return 0;
}

#include<iostream.h>
void main()
{
double a,c,d,e,f,g,h,k,w,p,q,r,s;
cout<<"欢迎使用利息计算器！"<<endl;
cout<<"请输入存款金额：";
cin>>a;
cout<<"======存款期限======"<<endl;
cout<<"1.3个月"<<endl;
cout<<"2.6个月"<<endl;
cout<<"3.一年"<<endl;
cout<<"4.二年"<<endl;
cout<<"5.三年"<<endl;
cout<<"6.五年"<<endl;
int b;
cout<<"请输入存款期限的代号：";
cin>>b;
c=a*0.031*0.25;
k=a+c;
d=a*0.033*0.5;
w=a+d;
e=a*0.035*1;
p=a+e;
f=a*0.044*2;
q=a+f;
g=a*0.050*3;
r=a+g;
h=a*0.055*5;
s=a+h;
switch(b)
{case 1:cout<<"到期利息为："<<c<<"元，本息合计共"<<k<<"元。\n";break;
case 2:cout<<"到期利息为："<<d<<"元，本息合计共"<<w<<"元。\n";break;
case 3:cout<<"到期利息为："<<e<<"元，本息合计共"<<p<<"元。\n";break;
case 4:cout<<"到期利息为："<<f<<"元，本息合计共"<<q<<"元。\n";break;
case 5:cout<<"到期利息为："<<g<<"元，本息合计共"<<r<<"元。\n";break;
case 6:cout<<"到期利息为："<<h<<"元，本息合计共"<<s<<"元。\n";break;
default:cout<<"error\n";break;
}
cout<<"感谢您的使用，欢迎下次光临！"<<endl;
}

#include<iostream.h>
#include<cmath>
void main()
{
double x,y;
cout<<"请输入x的值:";
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的值是："<<y<<endl;

}