public static void main(String[] args)throws Exception {

Scanner sc =new Scanner(new File("/home/mao/workspace/面试/JavaGuide/JavaInterview/java/src/ByteDancePreparation/main_3"));

//Scanner sc =new Scanner(System.in);

while(sc.hasNext()){

int n=sc.nextInt();

List<Integer> d=new ArrayList<>();

List<List<Integer>> dp=new ArrayList<>(n+1);

for (int i=0;i<n+1;i++){

dp.add(new ArrayList<>());

}

for (int i = 1; i <=n ; i++) {

d.add(sc.nextInt());

}

for (int i = 1; i <=n ; i++) {

dp.get(i).set(i,d.get(i-1));

}

for (int e=1;e<=n;e++){

for(int s=e-1;s>=1;s--){

if(e-s==1){

dp.get(s).set(e,Math.max(d.get(s-1),d.get(e-1)));

}else {

dp.get(s).set(e,Math.max(d.get(s-1)+Math.min(dp.get(s+2).get(e),dp.get(s+1).get(e-1)),d.get(e-1)+Math.min(dp.get(s).get(e-2),dp.get(s+1).get(e-1))));

}

}

}

System.out.println(dp.get(1).get(n));

}

}