content: package v108;
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.io.PrintWriter;
  import java.util.StringTokenizer;
  
  public class GameOfSum_UVa10891 {
  
  	static final int INF = (int)2e9;
  	static int N, A[];
  	static Integer memo[][][];
  	
  	static int dp(int t, int i, int j)
  	{
  		if(i == j)
  			return A[i];
  		if(i > j)
  			return 0;
  		if(memo[t][i][j] != null)
  			return memo[t][i][j];
  		int ret = -INF;
  		for(int k = i, sum = 0; k <= j; ++k)
  		{
  			sum += A[k];
  			ret = Math.max(ret, sum - dp(t ^ 1, k + 1, j));
  		}
  		for(int k = j, sum = 0; k >= i; --k)
  		{
  			sum += A[k];
  			ret = Math.max(ret, sum - dp(t ^ 1, i, k - 1));
  		}
  		return memo[t][i][j] = ret;
  	}
  	
  	public static void main(String[] args) throws Exception 
  	{
  		Scanner sc = new Scanner(System.in); 
  		PrintWriter out = new PrintWriter(System.out);
  
  		while(true)
  		{
  			N = sc.nextInt();
  			if(N == 0)
  				break;
  			A = new int[N];
  			for(int i = 0; i < N; ++i)
  				A[i] = sc.nextInt();
  			
  			memo = new Integer[2][N][N];
  			out.println(dp(0, 0, N - 1));
  		}
  
  		out.flush();
  		out.close();
  	}
  
  	static class Scanner 
  	{
  		StringTokenizer st;
  		BufferedReader br;
  
  		public Scanner(InputStream s){	br = new BufferedReader(new InputStreamReader(s));}
  
  		public String next() throws IOException 
  		{
  			while (st == null || !st.hasMoreTokens()) 
  				st = new StringTokenizer(br.readLine());
  			return st.nextToken();
  		}
  
  		public int nextInt() throws IOException {return Integer.parseInt(next());}
  
  		public long nextLong() throws IOException {return Long.parseLong(next());}
  
  		public String nextLine() throws IOException {return br.readLine();}
  
  		public double nextDouble() throws IOException
  		{
  			String x = next();
  			StringBuilder sb = new StringBuilder("0");
  			double res = 0, f = 1;
  			boolean dec = false, neg = false;
  			int start = 0;
  			if(x.charAt(0) == '-')
  			{
  				neg = true;
  				start++;
  			}
  			for(int i = start; i < x.length(); i++)
  				if(x.charAt(i) == '.')
  				{
  					res = Long.parseLong(sb.toString());
  					sb = new StringBuilder("0");
  					dec = true;
  				}
  				else
  				{
  					sb.append(x.charAt(i));
  					if(dec)
  						f *= 10;
  				}
  			res += Long.parseLong(sb.toString()) / f;
  			return res * (neg?-1:1);
  		}
  
  		public boolean ready() throws IOException {return br.ready();}
  
  		public boolean nextEmpty() throws IOException
  		{
  			String s = nextLine();
  			st = new StringTokenizer(s);
  			return s.isEmpty();
  		}
  	}
  }