#include<iostream>
#include<string>
#include<algorithm>
#include<cctype>
#include<set>
#include<bitset>
#include<math.h>
#include<map>
#include<queue>
#include<iomanip>
using namespace std;

int main(){
    int n, temp, sum1 = 0, y;
    cin >> n;
    vector<int> v(n);
    for (int i = 0; i < n; i++){
        cin >> temp;
        sum1 += temp;
    }
    cin >> y;
    cout << sum1 - y << endl;
}