#pragma comment(linker,"/STACK:64000000")
#include <stdio.h>
#include <iostream>
#define _USE_MATH_DEFINES
#include <math.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <string>

using namespace std;

#define mp make_pair
#define pb push_back
#define eps (double)(1e-9)
#define MOD (int)(1e9+7)

typedef long long ll;
typedef unsigned long long ull;

int ans[(int)(1 << 20)];
int beat[(int)(1 << 20)];
int a[20];
vector<vector<int>> Sc(21);
int bit(int x)
{
    int res = 0;
    while (x)
    {
        res++;
        x &= x - 1;
    }
    return res;
}
int for_beat(int n, int x)
{
    int res = 0;
    int j = 0;
    while (j < n)
    {
        if (x & 1)
            res += a[j];
        x >>= 1;
        j++;
    }
    return res;
}
vector<int> st;
vector<int> hod;
int main()
{
#ifdef _DEBUG
    freopen("input.txt", "rt", stdin);
    freopen("output.txt", "wt", stdout);
#endif
    int n, i, j;
    scanf("%d", &n);
    for (i = 0; i < n; ++i)
        scanf("%d", &a[i]);
    j = 1;
    for (i = 0; i < 25; ++i)
    {
        st.pb(j);
        j *= 2;
    }
    int lg = st[n];
    memset(ans, -1, sizeof(ans[0])*lg);
    ans[0] = 0;
    j = 0;
    j = st[0] | st[1] | st[n - 1];
    hod.pb(j);
    j = st[0] | st[n - 1] | st[n - 2];
    hod.pb(j);
    j = st[0] | st[1] | st[2];
    for (i = 1; i < n - 1; ++i)
    {
        hod.pb(j);
        j <<= 1;
    }
    for (i = 0; i < n; ++i)
        ans[st[i]] = 0;
    for (i = 1; i < lg; ++i)
    {
        j = bit(i);
        Sc[j].pb(i);
        beat[i] = for_beat(n, i);
    }
    for (int level = 2; level <= n; ++level)
    {
        for (i = 0; i < Sc[level].size(); ++i)
        {
            int mn = (int)(1e9);
            for (j = 0; j < n; ++j)
            {
                int k = Sc[level][i] & (~hod[j]);
                if (ans[k] != -1)
                    mn = min(mn, beat[k] + ans[k]);
            }
            ans[Sc[level][i]] = mn;
        }
    }
    printf("%d", ans[lg - 1]);
    return 0;
}