#include <bits/stdc++.h>
#define FOR(i,bg,ed) for(ll i=(bg);i<(ed);i++)
#define REP(i,n) FOR(i,0,n)
#define MOD 1000000007
#define int long long
using namespace std;
typedef long long ll;
const int INF = 1e9;



signed main()
{
    int N, A, sum = 0, v;
    cin >> N;
    REP(i,N) {
        cin >> A;
        sum += A;
    }
    cin >> v;
    
    cout << sum - v << endl;
}