#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, s, x;
  cin >> n >> s;
  s -= n - 1;
  for (int i = 1; i <= n; i++) {
    cin >> x;
    s -= x;
  }
  if (s)
    cout << "NO";
  else
    cout << "YES";
}
