#include <bits/stdc++.h>
using namespace std;
int main(void) {
  int a[3], Nmax = 0;
  cin >> a[0] >> a[1] >> a[2];
  sort(a, a + 3);
  if (a[2] == (a[1] + a[0])) {
    cout << "NO";
  } else {
    cout << "YES";
  }
  return 0;
}
