#include <bits/stdc++.h>
int main() {
  int n, m;
  while (~scanf("%d%d", &n, &m)) {
    int ans = 0, a, i;
    for (i = 0; i < n; i++) {
      scanf("%d", &a);
      ans += a;
    }
    if (ans + n - 1 == m)
      printf("YES\n");
    else
      printf("NO\n");
  }
  return 0;
}
