#include <iostream>

#include <cstdio>

#include <cstdlib>

#include <cmath>

#include <algorithm>

#include <climits>

#include <cstring>

#include <string>

#include <set>

#include <map>

#include <queue>

#include <stack>

#include <vector>

#include <list>

#include <ext/rope>

#define rep(i,m,n) for(i=m;i<=n;i++)

#define rsp(it,s) for(set<int>::iterator it=s.begin();it!=s.end();it++)

#define vi vector<int>

#define pii pair<int,int>

#define mod 1000000007

#define inf 0x3f3f3f3f

#define pb push_back

#define mp make_pair

#define fi first

#define se second

#define ll long long

#define pi acos(-1.0)

const int maxn=1e3+;

const int dis[][]={,,-,,,-,,};

using namespace std;

using namespace __gnu_cxx;

ll gcd(ll p,ll q){return q==?p:gcd(q,p%q);}

ll qpow(ll p,ll q){ll f=;while(q){if(q&)f=f*p;p=p*p;q>>=;}return f;}

int n,m,dp[maxn][maxn],a[maxn],sum[maxn];

int main()

{

    int i,j,k,t;

    scanf("%d",&n);

    rep(i,,n)scanf("%d",&a[i]),dp[i][]=a[i],sum[i]=sum[i-]+a[i];

    rep(i,,n)

    {

        for(j=;j+i-<=n;j++)

        {

            dp[j][i]=max(sum[j+i-]-sum[j-]-dp[j][i-],sum[j+i-]-sum[j-]-dp[j+][i-]);

        }

    }

    printf("%d\n",dp[][n]);

    //system("pause");

    return ;

}