#include <iostream>
#include <cmath>
#include <vector>
#include <map>
#include <iomanip>
#include <algorithm>
#include <sstream>
#include <string>
#include <math.h>
#include <set>
#include <deque>
#include <queue>
#include <list>
using namespace std;
typedef long long ll;
const int mod = 1000000007;

#define for1(n) for (int i = 0 ; i < n ; i++)
#define for2(n) for (int j = 0 ; j < n ; j++)
#define for3(n) for (int k = 0 ; k < n ; k++)
#define for4(n) for (int l = 0 ; l < n ; l++)
#define forl(n) for (ll i = 0 ; i < n ; i++)

int main() {
    ios::sync_with_stdio(false);
    int n, b = 0;
    cin >> n;
    int a[n];
    for1(n) {
		cin >> a[n];
	    b += a[n];
	}
	cout << c - n;
}