c#

public static int hourglassSum(List> arr) { int max=Int32.MaxValue*-1;

    for(int v=0;v<4;v++){
        for(int h=0;h<4;h++){

            int sum = 0;

            sum += arr[v][h]   + arr[v][h+1]   + arr[v][h+2];
            sum +=               arr[v+1][h+1];
            sum += arr[v+2][h] + arr[v+2][h+1] + arr[v+2][h+2]; 

            if(sum>max)
            {
                max=sum;
            }               
        }
    }

    return max;
}