#include <iostream>
#include <string>
using namespace std;
 
int main()
{
    int N;
    cin >> N;
    long long sum = 0;
    long long n;
    while(N-->0){
        cin >> n;
        sum += n;
    }
    long long ans;
    cin >> ans;
 
    cout << sum - ans << endl;
}