#include <bits/stdc++.h>
using namespace std;
signed main() {
  long long a, b;
  cin >> a >> b;
  long long arr[a];
  long long sum = 0;
  for (long long i = 0; i < a; i++) {
    cin >> arr[i];
    sum += arr[i];
  }
  if (a == 1) {
    if (arr[0] == b || arr[0] == 0)
      cout << "YES";
    else
      cout << "NO";
    return 0;
  }
  if (sum == b - (a - 1))
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
