Check if a year is a leap year.

//Program to check if a year is a leap year.
#include<iostream.h>
#include<conio.h>
void main()
{
    clrscr();
    int a,b;
    cout<<"Enter a year: ";
    cin>>a;
    if(a%400==0)
    cout<<"It's a leap year"<<endl;
    else if(a%100==0)
    cout<<"It's not a leap year"<<endl;
    else if(a%4==0)
    cout<<"It's a leap year"<<endl;
    else
    cout<<"It's not a leap year"<<endl;
    getch();
}