#include <bits/stdc++.h>
int main() {
  int n;
  int a[1000];
  while (scanf("%d", &n) != EOF && n) {
    for (int i = 0; i < n; i++) {
      int x;
      scanf("%d", &x);
      a[i] = x - 1;
    }
    int sum = 0;
    for (int i = 0; i < n; i++) {
      sum += a[i];
    }
    printf("%d\n", sum);
  }
}
