#include <iostream>
#include <algorithm> 
using namespace std;

int main(){
	int n;
	cin >> n;
	while(n != 0){
		int a[n];
		for(int i = 0; i < n; i++){
			cin >> a[i];
		}

		sort(a.begin(), a.end());
		int sum = 0;
		for(int i = 0; i < n; i++){
			if(a[n-1-i] > 0){
				sum += a[n-1-i];
			}else{
				cout << sum << endl;
				break;
			}
		}
		cin >> n;
	}

	return 0;
}