private static int counter(int A[])
    {
         int sum;
         int e = A.length;
         int count = 0;
         for (int i=0; i<e; i++)
         {
             for (int j=i+1; j<e; j++)
             {
                 sum=A[i]+A[j];
                 if (-sum==binarySearch(A,sum))
                 {
                     count++;
                 }
             }
         }
         return count;