#include<bits/stdc++.h>
using namespace std;
int main(){
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    int s = a + b + c + d;
    if(a == s - a){
        cout << "Yes";
        return 0;
    }
    if(b == s - b){
        cout << "Yes";
        return 0;
    }
    if(c == s - c){
        cout << "Yes";
        return 0;
    }
    if(d == s - d){
        cout << "Yes";
        return 0;
    }
    if(a + b == c + d){
        cout << "Yes";
        return 0;
    }
    if(a + c == b + d){
        cout << "Yes";
        return 0;
    }
    if(a + d == c + b){
        cout << "Yes";
        return 0;
    }
    else cout << "No";
}