#include <bits/stdc++.h>
#define pb push_back
#define inf INFINITY
#define mp make_pair

using namespace std;
typedef long long ll;
const int MAX = 1e6 + 10;
const int MIN = 1e3 + 10;
const int MAXI = INT_MAX;
const int MAXL = 1e17 + 10;

int dp[MIN][MIN][2], arr[MAX];
int n;

int bt (int l, int r, bool t) {
    if (l == r)
        return t ? arr[l] : 0;
    if (dp[l][r][t] != -1) return dp[l][r][t];
    int ret = 0;
    int a,b;
    a=b=0;
    if (t)
        ret += max(bt(l + 1, r, 0) + arr[l], bt(l, r - 1, 0) + arr[r]);
    else
       {
             a=bt(l + 1, r, 1)+arr[l];
             b=bt(l, r - 1, 1)+arr[r];
           ret += max(a,b);
       }
        if(!t)
        {
            if(a>b)ret-=arr[l];
            else ret-=arr[r];
        }
    dp[l][r][t] = ret;
    return ret;
}

int main ()
{
    cin >> n;
    for (int i = 1; i <= n; i++)
        cin >> arr[i];
    memset(dp, -1, sizeof(dp));
    int ans = bt(2, n, 0) + arr[1];
    ans = max(ans, bt(1, n - 1, 0) + arr[n]);
    cout << ans << endl;
    return 0;
}