#include <bits/stdc++.h>
using namespace std;

int main(){
  int N, M, K;
  cin >> N >> K >> M;
  int sum=0;
  int purpose = M*N;
  for(int i=0; i<N-1; i++){
    int x;
    cin >> x;
    sum+=x;
  }
  if(purpose - sum <=K){
    if(purpose-sum >=0){
      cout << purpose-sum << endl;
    }else
    {
      cout << 0 << endl;
    }
    
  }
  if(purpose-sum>K)cout << -1 << endl;
  return 0;
}
#include <bits/stdc++.h>
using namespace std;

static const auto do_fast_io = [] {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    return nullptr;
}();

int main() {
    int a, b, c;
    cin >> a >> b >> c;
    long long req = (a * a) + (b * b);
    if (req < c * c) {
        cout << "Yes";
    } else {
        cout << "No";
    }
    return 0;
}