#include <bits/stdc++.h>
using namespace std;

int main() {
	// your code goes here
	long long x,a,y,b;
	cin>>x>>a>>y>>b;
    long long i = pow(x,a);
    long long j = pow(y,b);
    long long mx = 0,mn = 0;
    if(i>j){
        mx = i;
        mn = j;
    }
    else{
        mx = j;
        mn = i;
    }
    if((i==j)||(mx%mn==0)){
        cout<<"YES"<<endl;
    }
    else{
            cout<<"NO"<<endl;
        }
    
    
	return 0;
}