#include <bits/stdc++.h>
int main() {
  int i, j, n, x, len = 0;
  scanf("%d %d", &n, &x);
  int arr[n];
  for (i = 0; i < n; i++) {
    scanf("%d", &arr[i]);
    len += arr[i];
  }
  len += n - 1;
  if (x == len)
    printf("YES\n");
  else
    printf("NO\n");
  return 0;
}
