#include <bits/stdc++.h>

using namespace std;

// vjudge.net/contest/456753#problem/A

int main() {
    int n = 4;
    vector<int> v(n);
    for (int i = 0; i < n; ++i) {
        cin >> v[i];
    }

    for (int msk = 0; msk < (1 << n); ++msk) {
        int sum1 = 0, sum2 = 0;
        for (int i = 0; i < n; ++i) {
            if ((1 << i) & msk) {
                sum1 += v[i];
            } else {
                sum2 += v[i];
            }
        }
        if (sum1 == sum2)
        {
            puts("Yes");
            return 0;
        }
    }
    
    puts("No");


}