#include <bits/stdc++.h>
using namespace std;
int main(){
    long long h,w,n,k;
    cin>>h>>w>>n>>k;
    long long m=h*w%n;
    if(m==k||m==0&&k==n)
        cout<<"YES"<<endl;
    else
        cout<<"NO"<<endl;
    return 0;
}