#include <iostream>

#define rep(i,a,b) for(int i=a;i<b;i++)

using namespace std;

int main()
{
	int n, v, t, sum=0;

	cin >> n;
	rep(i, 0, n) {
		cin >> t;
		sum += t;
	}
	cin >> v;

	cout << sum - v << endl;

}