44 58 90 53
 20 14 37 71
 4 2 4 2
 1 2 5 5
 1 2 8 9
 99 100 3 98
 92 69 83 97
 3 1 1 1
 18 88 18 18
 1 1 1 1
 69 7 44 30
 90 30 30 30
 1 2 3 5
 1 1 3 1
 6 3 6 6
 26 52 7 19
 6 4 8 6
 10 2 3 5
 34 11 84 39
 1 1 14 12
 3 2 1 1
 2 4 6 6
 1 1 2 1
 72 96 2 26
 97 95 91 27
 1 2 1 3
 1 1 2 3
 1 1 1 2
 1 1 10 20
 2 3 2 5
 1 2 10 7
 2 1 28 9
 4 4 4 8
 2 2 4 6
 72 52 62 62
 76 97 99 74
 100 100 99 100
 30 74 41 63
 5 10 1 6
 18 17 17 20
 2 4 1 1
 7 3 6 3
 1 1 4 5
 2 2 6 2
 1 2 6 3
 3 5 1 3
 70 100 10 86
 48 14 3 31
 2 6 3 2
 2 3 10 10
 4 4 12 4
 14 9 10 6
 100 98 99 97
 5 7 1 3
 1 1 4 2
 14 10 18 24
 1 100 100 1
 1 2 4 5
 1 2 3 4
 1 2 3 3
 4 4 4 5
 66 68 16 82
 1 2 3 2
 2 3 3 4
 100 100 100 100
 1 2 2 7
 3 14 36 53
 1 1 3 4

NO
 YES
 YES
 NO
 YES
 NO
 NO
 YES
 NO
 YES
 NO
 YES
 NO
 YES
 NO
 YES
 YES
 YES
 YES
 YES
 NO
 NO
 NO
 YES
 NO
 NO
 NO
 NO
 NO
 NO
 YES
 NO
 NO
 NO
 YES
 YES
 NO
 YES
 YES
 NO
 YES
 NO
 NO
 YES
 YES
 YES
 NO
 YES
 NO
 NO
 YES
 NO
 YES
 YES
 YES
 NO
 YES
 YES
 YES
 NO
 NO
 NO
 YES
 YES
 YES
 NO
 YES
 NO

#include <bits/stdc++.h>
using namespace std;
long long add(long long a, long long b) {
  a += b;
  if (a >= 1000000007) {
    a -= 1000000007;
  }
  return a;
}
long long sub(long long a, long long b) {
  a -= b;
  if (a < 0) {
    a += 1000000007;
  }
  return a;
}
long long mul(long long a, long long b) { return (a * b) % 1000000007; }
void add_self(long long& a, long long b) { a = add(a, b); }
void sub_self(long long& a, long long b) { a = sub(a, b); }
void mul_self(long long& a, long long b) { a = mul(a, b); }
const long long MAXN = 200010;
int main() {
  ios_base ::sync_with_stdio(false);
  cin.tie(nullptr);
  long long a[4];
  long long tot = 0;
  for (long long i = 0; i < 4; i++) {
    cin >> a[i];
    tot += a[i];
  }
  for (long long i = 0; i < 4; i++) {
    for (long long j = i + 1; j < 4; j++) {
      if (tot - a[i] - a[j] == a[i] + a[j]) {
        cout << "YES"
             << "\n";
        return 0;
      }
    }
  }
  for (long long i = 0; i < 4; i++) {
    for (long long j = i + 1; j < 4; j++) {
      for (long long k = j + 1; k < 4; k++) {
        if (tot - a[i] - a[j] - a[k] == a[i] + a[j] + a[k]) {
          cout << "YES"
               << "\n";
          return 0;
        }
      }
    }
  }
  for (long long i = 0; i < 4; i++) {
    if (tot - a[i] == a[i]) {
      cout << "YES"
           << "\n";
      return 0;
    }
  }
  cout << "NO\n";
  return 0;
}
