c++作业3

一、多分数段函数求值

（1）代码

#include<stdio.h>
#include <math.h>
void main()
{
double x,y;
scanf("%d",&x);
if(x<2)
y=x;
else if(2<=x&&x<6)
y=x*x+1;
else if(6<=x&&x<10)
y=sqrt(x+1);
else
y=1/(x+1);
printf("%d",y);
}

（2）输出结果



二、本月有几天？

（1）代码

#include<iostream>
using namespace std;
int main()
{
int iYear,iMonth,iDay;
cout<<"请输入年份";
cin>>iYear;
cout<<"请输入月份";
cin>>iMonth;
if((iYear%4==0&&iYear%100!=0)||iYear%400==0)
{
switch(iMonth)
{
case 2:iDay=29;break;
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:iDay=31;break;
case 4:
case 6:
case 9:
case 11:iDay=30;break;
default:"error";break;
}
}
else
{
switch(iMonth)
{
case 2:iDay=28;break;
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:iDay=31;break;
case 4:
case 6:
case 9:
case 11:iDay=30;break;
default:"error";break;
}
}
cout<<iDay;
return 0;
}
（2）输出结果



三、定期存款利息计算器

（1）代码

#include<iostream>
using namespace std;
int main()
{
double iDeposit,iInterest,iSum;
int iNumber;
cout<<"欢迎使用利息计算器"<<endl;
cout<<"请输入存款的金额：";
cin>>iDeposit;
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;
cout<<"请输入存款期限的代号：";
cin>>iNumber;
switch(iNumber)
{
case 1:iInterest=iDeposit*0.031*0.25;iSum=iInterest+iDeposit;break;
case 2:iInterest=iDeposit*0.033*0.5;iSum=iInterest+iDeposit;break;
case 3:iInterest=iDeposit*0.035*1.0;iSum=iInterest+iDeposit;break;
case 4:iInterest=iDeposit*0.044*2.0;iSum=iInterest+iDeposit;break;
case 5:iInterest=iDeposit*0.05*3.0;iSum=iInterest+iDeposit;break;
case 6:iInterest=iDeposit*0.055*5.0;iSum=iInterest+iDeposit;break;
default:"error";break;
}
cout<<"到期利息为："<<iInterest<<"元，本息合计共"<<iSum<<"元。"<<endl;
cout<<"感谢您的使用，欢迎下次光临！";
return 0;
}

(2)输出结果