#include<bits/stdc++.h>
#define rep(i,a,n) for (int i = a;i < n;i++)
#define per(i,n,a) for (int i = n-1;i >= a;i--)
using namespace std;

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