UVA10891 Game of Sum

#include<bits/stdc++.h>
using namespace std;

const int MX = 101;
int d[MX][MX],f[MX][MX],g[MX][MX];
int sum[MX];

//#define LOCAL
int main()
{
#ifdef LOCAL
    freopen("in.txt","r",stdin);
#endif
    int n;
    while(scanf("%d",&n),n){
        for(int i = 1; i <= n; i++){
            scanf("%d",sum+i);
        }
        for(int i = 1; i <= n; i++){
            g[i][i] = f[i][i] = d[i][i] = sum[i];
            sum[i] += sum[i-1];
        }
        for(int L = 1; L < n; L++){
            for(int i = 1; i+L <= n; i++){
                int j = i+L;
                d[i][j] = sum[j] - sum[i-1] - min(0,min(f[i+1][j],g[i][j-1]));
                f[i][j] = min(d[i][j],f[i+1][j]);
                g[i][j] = min(d[i][j],g[i][j-1]);
            }
        }
        printf("%d\n",(d[1][n]<<1)-sum[n]);
    }
    return 0;
}