#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, x;
  long long int sum = 0;
  cin >> n >> x;
  for (int i = 0; i < n; i++) {
    int val;
    cin >> val;
    sum += val;
    sum++;
  }
  sum--;
  if (sum == x)
    cout << "YES\n";
  else
    cout << "NO\n";
  return 0;
}
