#include<iostream>
using namespace std;
int main(void)
{
	long int h, w, i;
	long int n, k;
	
	cin >> h >> w >> n >> k;
	if(h*w%n==0&&n==k|| h*w%n == k)
	cout << "YES" << endl;
	else cout << "NO" << endl;

	return 0;
}