#include <iostream>
#include <vector>
#include <algorithm>
#include <limits>
#include <stack>

using namespace std;

long long popcount(long long n) {
    long long c = (n & 0x5555555555555555) + ((n >> 1) & 0x5555555555555555);
    c = (c & 0x3333333333333333) + ((c >> 2) & 0x3333333333333333);
    c = (c & 0x0f0f0f0f0f0f0f0f) + ((c >> 4) & 0x0f0f0f0f0f0f0f0f);
    c = (c & 0x00ff00ff00ff00ff) + ((c >> 8) & 0x00ff00ff00ff00ff);
    c = (c & 0x0000ffff0000ffff) + ((c >> 16) & 0x0000ffff0000ffff);
    c = (c & 0x00000000ffffffff) + ((c >> 32) & 0x00000000ffffffff);
    return c;
}

struct StackElement {
    long long r;
    int c;
    int i;
};

int main() {
    int N;
    cin >> N;
    vector<int> R(N);
    for (int i = 0; i < N; ++i) {
        cin >> R[i];
    }

    if (N >= 26) {
        cout << 0 << endl;
        return 0;
    }

    vector<vector<long long>> dp(N + 1);
    stack<StackElement> stack;
    stack.push({0, 0, -1});

    while (!stack.empty()) {
        StackElement element = stack.top();
        stack.pop();
        dp[element.c].push_back(element.r);
        if ((element.c + 1) * 2 > N) {
            continue;
        }
        for (int j = element.i + 1; j < N; ++j) {
            stack.push({element.r + R[j], element.c + 1, j});
        }
    }

    long long ans = numeric_limits<long long>::max();
    for (int n = 1; n <= N; ++n) {
        if (2 * n > N) {
            break;
        }
        int le = dp[n].size();
        sort(dp[n].begin(), dp[n].end());
        for (int i = 0; i < le - 1; ++i) {
            ans = min(ans, dp[n][i + 1] - dp[n][i]);
        }
    }
    cout << ans << endl;
    return 0;
}