#include<iostream>
#include<iomanip>
#include<cmath>
#include<string>
#include<algorithm>
#include<vector>
#include<math.h>
#include<stack>
#include <typeinfo>  
using namespace std;
int main(void){
    int N, A, sum = 0; cin >> N;
    vector<int> v;
    for(int i = 0; i < N; i++){
        cin >> A;
        sum += A;
    }
    int F; cin >> F;
    cout << sum - F << endl;
    return 0;
}