#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, x, y, a;
  while (cin >> n >> x) {
    y = 0;
    for (int i = 0; i < n; i++) {
      cin >> a;
      y += a;
      y++;
    }
    if (y - 1 == x)
      cout << "YES" << endl;
    else
      cout << "NO" << endl;
  }
  return 0;
}
