#include <iostream>
#include <vector>

int main()
{
  int N;
  std::cin >> N;
  std::vector<int> a(N);
  for (int i = 0; i < N; i++)
  {
     int x;
     std::cin >> x;
     a[i] = x - 1;
  }

  int sum = 0;
  for (auto it = a.begin(); it != a.end(); i++)
    sum += *it;

  std::cout << sum << std::endl;
}