#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using P = pair<int, int>;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  ll n;
  cin >> n;
  vector<ll> a(n);
  for (ll i = 0; i < (ll)n; i++) cin >> a[i];
  ll ans = 0;
  for (ll i = 1; i < (ll)100010; i++) {
    ans += a[i] - 1;
  }
  cout << ans << endl;
  return 0;
}
