#include<bits/stdc++.h>

#define int long long
#define pb push_back
#define fi first
#define se second
using namespace std;
using ll = long long;
using ld = long double;
using ull = unsigned long long;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int maxN = 1e6 + 5;
const int mod = 1e9 + 7;
const ll oo = 1e18;
int n, a[maxN];
int sum[maxN];
int f[maxN];
void ReadInput()
{
    cin >> n;
    for(int i=1; i<=n; i++)
        cin >> a[i];
    for(int i=1; i<=n; i++)
        sum[i] = sum[i - 1] + a[i];
}
void Solve()
{
    memset(f, 3, sizeof f);
    f[0] = 0;
    for(int i=1; i<=n; i++)
    {
        int low = 0, high = i - 1, mid;
        while(low <= high)
        {
            mid = (low + high) / 2;
            if(f[mid] + sum[mid] <= sum[i]) low = mid + 1;
            else high = mid - 1;
        }
        f[i] = sum[i] - sum[high];
    }
    int res = oo;
    for(int i=1; i<=n; i++)
        res = min(res, max(f[i], sum[n] - sum[i]));
    cout << res;
}
#define taskname "sol"
int32_t main()
{
    if (fopen(taskname ".inp", "r"))
    {
        freopen(taskname ".inp", "r", stdin);
       // freopen(taskname ".out", "w", stdout);
    }
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int T = 1;
    //cin >> T;
    for(int itest=1; itest<=T; itest++)
    {
        ReadInput();
        Solve();
    }
}