#include <iostream>
#include <vector>
#include <limits>

using namespace std;

bool next_binary(vector<bool> &bin)
{
    int n = bin.size() - 1;

    while (n >= 0 && bin[n]) {
        bin[n] = 0;
        n--;
    }

    if (n == -1) {
        return false;
    }

    bin[n] = 1;

    return true;
}

double fair_division(const vector<double> &a)
{
    const int n = a.size();

    double min_diff = numeric_limits<double>::max();

    vector<bool> d(n);
    do {
        double sum_A = 0, sum_B = 0;
        for (int i = 0; i < n; i++) {
            if (d[i]) {
                sum_B += a[i];
            } else {
                sum_A += a[i];
            }
        }
        min_diff = min(min_diff, abs(sum_B - sum_A));
    } while (next_binary(d));

    return min_diff;
}

int main(void)
{
    int n;
    cin >> n;

    vector<double> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }

    cout << fair_division(a) << endl;
    
    return 0;
}