100%AC

#include<cstdio>
int main(){
    int y;
    scanf("%d",&y);
    printf(y%4==0&&y%100!=0||y%400==0?"yes":"no");
}

#include<iostream>
using namespace std;

int main(){
    int y;
    cin>>y;
    if(y%4==0)
    {
        if(y%100==0)
        {
            if(y%400==0)
            {
                cout<<"yes"<<endl;
            }
            else
            {
                cout<<"no"<<endl;
            }
        }
        else
        {
            cout<<"yes"<<endl;
        }
    }
    else
    {
        cout<<"no"<<endl;
    }
    return 0;
}