#include <bits/stdc++.h>
using namespace std;
using pint = pair< int, int >;

int main()
{
    int n = 0, v = 0;
    cin >> n;
    
    vector< int > vec( n );
    
    for( auto&& i : vec ) {
        cin >> i;
    }
    
    cin >> v;
    
    cout << ( accumulate( begin( vec ), end( vec ), 0 ) - v ) << endl;
}