#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <iomanip>
#include <cmath>
#include <functional>
using namespace std;
#define diff(x,y) ((x > y) ? (x - y) : (y - x))
#define us(x) (x > 0) ? x : x * -1
#define lli long long int
const int MAX = 10000001;

int main() {
	int n, x;
	lli num = 0, v;
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> x;
		num += x;
	}
	cin >> v;
	cout << num - v << endl;
	return 0;
}