#include <vector>
#include <string>
#include <algorithm>
#include <numeric>
#include <iostream>
#include <cstdlib>
#include <cstring>
#include <utility>
#include <list>
#include <map>
#include <iterator>
using namespace std;

using ull = unsigned long long;
using ll = long long;

int main()
{
    int n;
    cin >> n;
    vector<ll>  data(n);

    for(auto&& x : data) cin >> x;
    ll v;
    cin >> v;

    ll sum = accumulate(data.begin(),data.end(),0);

    cout << sum - v << endl;
}