#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

int kadens(int *a, int size, int *x, int *y)
{
    int max_so_far = INT_MIN, max_ending_here = 0,
       start =0, end = 0, s=0;
 
    for (int i=0; i< size; i++ )
    {
        max_ending_here += a[i];
 
        if (max_so_far < max_ending_here)
        {
            max_so_far = max_ending_here;
            start = s;
            end = i;
        }
 
        if (max_ending_here < 0)
        {
            max_ending_here = 0;
            s = i + 1;
        }
    }
    
    *x=start;
    *y=end;
    return  max_so_far;   
   
}


void invert(int *a, int n){
    for(int i=0;i<n;i++){
        a[i]=a[i]*(-1);
    }
}

long int find(int *a, int n, int x, int y){
    long int ans=0;
    for(int i=x;i<y;i++){
        for(int j=i+1;j<=y;j++){
            ans=ans + a[i]*a[j];
        }
    }return ans;
}
long int largestValue(int n, int* a) {
    // Return the largest value of any of A's nonempty subarrays.
    int i=0,j=0,x=0,y=0;  int max1, max2;
    max1=kadens(a,n,&i,&j);
    //printf("%d %d %d\n",i,j,max1);
    invert(a,n);
    max2=kadens(a,n,&x,&y); 
    // printf("%d %d %d\n",x,y,max2);
    long int res=0;
    if(max1<max2){
        res=find(a,n,x,y);
    }else{
        invert(a,n);
        res=find(a,n,i,j);
    }
    return res;
}

int main() {
    int n; 
    scanf("%i", &n);
    int *A = malloc(sizeof(int) * n);
    for (int A_i = 0; A_i < n; A_i++) {
       scanf("%i",&A[A_i]);
    }
    long int result = largestValue(n, A);
    printf("%ld\n", result);
    return 0;
}