#include <bits/stdc++.h>
using namespace std;
int solve(int arr[], int n, int x) {
  int tmp = 0;
  for (int i = 0; i < n; i++) {
    tmp += x % arr[i];
  }
  return tmp;
}
int main() {
  int n;
  cin >> n;
  int arr[n];
  long int ans = 0;
  int mi = INT_MAX;
  int ma = INT_MIN;
  for (int i = 0; i < n; i++) {
    cin >> arr[i];
    ans += arr[i] - 1;
  }
  cout << ans << "\n";
}
