#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <iomanip>
#include <stack>
#include <algorithm>
#include <string>
#include <map>
#include <iterator>
#include <set>
#include <queue>

using namespace std;


int main() {

   int N;
   cin>>N;

    long s = 0;
    for (int i = 0; i < N; ++i) {
        long A;
        cin>>A;
        s += A;
    }
    long v;
    cin >> v;

    cout << s - v << endl;


    return 0;
}