import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Scanner;
public class Array {
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
int a = sc.nextInt();
int b = sc.nextInt();
int c = sc.nextInt();
int d = sc.nextInt();
int[] array_number = {a,b,c,d};
int count = 0;
for(int number : array_number)
{
if(number > 0)
{
count++;
}
}
if(count == 2)
{
System.out.println("YES");
}
else
{
System.out.println("NO");
}
}
}
