#include <bits/stdc++.h>

using namespace std;

int main() {
  int n;
  cin >> n;
  int sum = 0;
  for (int i = 0; i < n; ++i) {
    int a;
    cin >> a;
    sum += a;
  }

  int v;
  cin >> v;
  cout << sum - v << '\n';
  return 0;
}