#include <iostream>
#include <string>
#include <algorithm>

using namespace std;

int main()
{
    int n, a, v, sum = 0;
    cin >> n;

    for(int i=0; i<n; i++){
        cin >> a;
        sum += a;
    }
    cin >> v;

    cout << sum - v << endl;

    return 0;
}