#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define endl "\n"

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

    cout << sum - v << endl;

    return 0;
}