#include <stdio.h>
#include <algorithm>
using namespace std;
using ll = long long;

//369
int main() {
	int n, a, total = 0, u;
	scanf("%d", &n);
	for (int i = 0; i < n; i++) {
		scanf("%d", &a);
		total += a;
	}
	scanf("%d", &u);
	printf("%d\n", total - u);
}