#include <bits/stdc++.h>
using namespace std;
static int n, x;
static vector<int> ve;
int main() {
  while (scanf("%d%d", &n, &x) != EOF) {
    ve.clear();
    ve.resize(n, 0);
    int cnt = 0;
    for (int i = 0; i < n; i++) {
      scanf("%d", &ve[i]);
      cnt += ve[i] + 1;
    }
    if (cnt - 1 == x) {
      printf("YES\n");
    } else {
      printf("NO\n");
    }
  }
  return 0;
}
