ارسال شماره 1,003

import java.util.*;
class Main {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        List<Integer> list = new ArrayList<>();

        for (int i = 0; i < 4; i++) {
            list.add(sc.nextInt());
        }

        list.sort(Collections.reverseOrder());

        System.out.println(Objects.equals(list.get(0), list.get(1)) && Objects.equals(list.get(2), list.get(3)) ? "YES" : "NO");


    }
}