#include <bits/stdc++.h>
using namespace std;
 
using ll = long long; using ld = long double; using ull = unsigned long long; using uint = unsigned int;
using vi  = vector<int>; using vb  = vector<bool>; using vd  = vector<double>; using vl  = vector<ll>;
using vvi = vector<vi>;  using vvb = vector<vb>;   using vvd = vector<vd>;     using vvl = vector<vl>;
 
#define REP(i,n) for(ll i=0; i<(n); ++i)

int main() {
	cin.tie(0);
	ios_base::sync_with_stdio(false);
	cout << fixed << setprecision(30);
	ll n; cin >> n;
	vl a(n); REP(i, n) cin >> a[i];
	ll w; cin >> w;
	ll sum = 0; REP(i, n) sum += a[i];
	cout << sum - w << endl;
	return 0;
}