#include <bits/stdc++.h>
using namespace std;
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  int a, b, c;
  cin >> a >> b >> c;
  if (a == b + c) {
    cout << "yes" << endl;
  } else if (b == a + c) {
    cout << "yes" << endl;
  } else if (c == a + b) {
    cout << "yes" << endl;
  } else {
    cout << "no" << endl;
  }
}
