#include<iostream>
#include<vector>
#include<string>
#include<cstdio>
#include<algorithm>
using namespace std;
int main(){
    int x,y,N,sum=0;
    cin >> N;
    while(N--){
        cin >> x;
        sum += x;
    }
    cin >> y;
    cout << sum-y;
    return 0;
}