#include <bits/stdc++.h>
using namespace std;

template <class T1, class T2>
inline bool minimise(T1 &x, T2 y) {
	if (x > y) { x = y; return true; }
	return false;
}

template <class F>
inline int FIND_SMALLEST(int l, int r, F f) {
	int res = r + 1;
	while (l <= r) {
		int m = (l + r) >> 1;
		if (f(m)) res = m, r = m - 1;
		else l = m + 1;
	}
	return res;
}

template <class F>
inline int FIND_LARGEST(int l, int r, F f) {
	int res = l - 1;
	while (l <= r) {
		int m = (l + r) >> 1;
		if (f(m)) res = m, l = m + 1;
		else r = m - 1;
	}
	return res;
}

const int MAX = 1e5 + 7;
int N, pre[MAX];

void input() {
	cin >> N;
	pre[0] = 0;
	for (int i = 1; i <= N; i++) {
		cin >> pre[i];
		pre[i] += pre[i - 1];
	}
}

// x1 - x0 <= x2 - x1 <= x3 - x2 <= x4 - x3 <= ...

void solve() {
	int ans = pre[N];
	for (int i = N; i >= 1; i--) {
		int j = FIND_LARGEST(0, i, [&](int j) {
			int sum = pre[i] - pre[j];
			while (j > 0) {
				int k = FIND_SMALLEST(0, j - 1, [&](int k) {
					return pre[j] - pre[k] <= sum;
				});

				if (k >= j)
					return false;

				sum = pre[j] - pre[k];
				j = k;
			}
			return j == 0;
		});

		minimise(ans, max(pre[i] - pre[j], pre[N] - pre[i]));
	}

	cout << ans;
}
	
int main(void) {
	ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);

	input();
	solve();

	return 0;
}