конь

#include <iostream>
#include <fstream>
#include <cmath>
#include <math.h>


using namespace std;

int a, b, c, d;

int main(int argc, const char * argv[]) {

    cin >> a >> b >> c >> d;
    if (a / c == b / d){
    	cout << "YES";
    	return 0 ;
    }
    if (a / c == d / b){
    	cout << "YES";
    	return 0 ;
    }
    if (c / a == b / d){
    	cout << "YES";
    	return 0 ;
    }
    if (c / a == d / b){
    	cout << "YES";
    	return 0 ;
    }
    else {
    	cout << "NO";
    	return 0;
    }
}