#include <iostream>
#include <cstring>
#include <algorithm>
#include <bits/stdc++.h>
#define ll long long
using namespace std;
void ctt(int arr[],int n,int i,int j,int p){
if(n==0){
cout<<p;
return;
}
if(n==1){
p+=arr[i];
cout<<p;
return;
}
else{
if(arr[i]>=arr[j]){
//cout<<arr[i]<<" "<<arr[j]<<" "<<i<<" "<<j<<" a"<<"\n";
p+=arr[i++];
if(arr[i]>=arr[j]){
ctt(arr,n-2,i+1,j,p);
}
else{
ctt(arr,n-2,i,j-1,p);
}
}
else{
//cout<<arr[i]<<" "<<arr[j]<<" "<<i<<" "<<j<<" b"<<"\n";
p+=arr[j--];
if(arr[i]>=arr[j]){
ctt(arr,n-2,i+1,j,p);
}
else{
ctt(arr,n-2,i,j-1,p);
}
}
}
}
int main()
{
int n;
cin >> n;
int t[n];
for(int i=0;i<n;i++){
cin >> t[i];
}
ctt(t,n,0,n-1,0);
}
