#include <iostream>
using namespace std;

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