#include <bits/stdc++.h>
using namespace std;
set<long long> st;
vector<pair<long long, char> > v;
set<long long>::iterator it;
multiset<long long> ms;
multiset<long long>::iterator mt;
deque<long long> dq;
map<long long, long long> mp;
long long q, n, a[100003], sum, x = 86400, m, ans;
string h;
int main() {
  ios::sync_with_stdio(0), cin.tie(NULL), cout.tie(NULL);
  cin >> n >> m;
  for (long long i = 1; i <= n; i++) cin >> a[i];
  for (long long i = 1; i <= n; i++) {
    sum += a[i];
  }
  if (m - sum + 1 == n)
    cout << "YES";
  else
    cout << "NO";
  return 0;
}
