#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, x, g;
  scanf("%d %d", &n, &x);
  long long S = 0;
  for (int i = 0; i < n; i++) {
    scanf("%d", &g);
    S += g + 1;
  }
  S--;
  if (S == x)
    cout << "YES";
  else
    cout << "NO";
}
