#include <iostream>

using namespace std;

int main() {
    int N;
    while (cin >> N) {
        if (N == 0) {
            break;
        }
        int result = 0;
        int val;
        for (int i = 0; i < N; i++) {
            cin >> val;
            result += val;
        }
        cout << result << endl;
    }
    return 0;
}