poj 2479

#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<cmath>
#include<cstdlib>
#include<algorithm>
using namespace std;
#define max(a,b) a>b?a:b
#define MAXV 50010
#define inf -10010

int lt[MAXV],rt[MAXV],a[MAXV],rtm[MAXV];

int main()
{
int t,n,i,temp;
scanf("%d",&t);
while(t--){
scanf("%d",&n);
for(i=1;i<=n;i++)
scanf("%d",&a[i]);

temp=inf;lt[1]=a[1];rt[n]=a[n];
for(i=2;i<=n;i++){
    lt[i]=max(a[i],lt[i-1]+a[i]);
}
for(i=n-1;i>=1;i--){
rt[i]=max(a[i],rt[i+1]+a[i]);
}

rtm[n]=rt[n];
for(i=n-1;i>=1;i--)
    rtm[i]=max(rtm[i+1],rt[i]);

int ma=inf;
for(i=2;i<=n;i++){
    ma=max(ma,lt[i-1]+rtm[i]);
}
printf("%d\n",ma);

}
return 0;
}