import java.util.*;

import org.omg.CORBA.WCharSeqHelper;

public class Main {
	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		long w = sc.nextLong();
		long h = sc.nextLong();
		long n = sc.nextLong();
		long k = sc.nextLong();
		if(w*h%n==k){
			System.out.println("YES");
		}else if(w*h%n==0&&k==n){
			System.out.println("YES");
		}else{
			System.out.println("NO");
		}
		
	}
}