判断某天是某年的第几天

/*

*Copyright (c)2013,烟台大学计算机学院

*All rights reserved.

*文件名称：test.cpp

*作者：孙玲倩

*完成日期：2013年11月13日

*版本号：v1.0

*问题描述：判断某天是某年的第几天

*问题分析：先判断某年是平年还是闰年再判断

*/

#include<iostream>
using namespace std;
int time(int,int,int);
int main()
{
int year,month,day,tian;
cout<<"请输入年月日："<<endl;
cin>>year>>month>>day;
tian=time(year,month,day);
cout<<year<<"年"<<month<<"月"<<day<<"日是本年的第"<<tian<<"天"<<endl;
return 0;
}
int time(int year,int month,int day)
{
int tian;
if(year%4==0&&year%100!=0||year%400==0)
{
switch(month)
{
case 1:tian=day;break;
case 2:tian=day+31;break;
case 3:tian=day+31+29;break;
case 4:tian=day+31+29+31;break;
case 5:tian=day+31+29+31+30;break;
case 6:tian=day+31+29+31+30+31;break;
case 7:tian=day+31+29+31+30+31+30;break;
case 8:tian=day+31+29+31+30+31+30+31;break;
case 9:tian=day+31+29+31+30+31+30+31+31;break;
case 10:tian=day+31+29+31+30+31+30+31+31+30;break;
case 11:tian=day+31+29+31+30+31+30+31+31+30+31;break;
case 12:tian=day+31+29+31+30+31+30+31+31+30+31+30;break;
}
return tian;
}
else
{
switch(month)
{
case 1:tian=day;break;
case 2:tian=day+31;break;
case 3:tian=day+31+28;break;
case 4:tian=day+31+28+31;break;
case 5:tian=day+31+28+31+30;break;
case 6:tian=day+31+28+31+30+31;break;
case 7:tian=day+31+28+31+30+31+30;break;
case 8:tian=day+31+28+31+30+31+30+31;break;
case 9:tian=day+31+28+31+30+31+30+31+31;break;
case 10:tian=day+31+28+31+30+31+30+31+31+30;break;
case 11:tian=day+31+28+31+30+31+30+31+31+30+31;break;
case 12:tian=day+31+28+31+30+31+30+31+31+30+31+30;break;
}
return tian;
}
}