#include <iostream>
using namespace std;
const char en='\n';
int main(){
	cin.tie();
	ios::sync_with_stdio(false);
	int a,b,sum,y;
	cin>>a;
	for(int i=0;i<a;++i){
		cin>>b;
		sum+=b;
	}
	cin>>y;
	cout<<sum-y<<en;
	return 0;
}