#include <iostream>
#include <vector>
#include <string>

#define REP(i, a, b) for (int i = int(a); i < int(b); i++)
#define dump(s) cerr << __LINE__ << "\t:" << #s << " = " << (s) << endl
    
using namespace std;

int main () {
    int N;
    cin >> N;
    int sum = 0;
    REP (i, 0, N) {
	int a;
	cin >> a;
	sum += a;
    }
    int v;
    cin >> v;
    cout << sum - v << endl;
    
    return 0; 
}