为什么输入2000年，按个回车，程序就退出来了

#include "stdafx.h"
#include<iostream>
using namespace std;
int main()
{
int year;
bool isLeapYear;
cout<<"Enter the year:";
cin>>year;
isLeapYear=((year%4==0&&year%100!=0)||(year%400==0));
if(isLeapYear)
cout<<year<<"is a Leap Year"<<endl;
else
cout<<year<<"is not a Leap Year"<<endl;
return 0;
}