static void quickSort(int arr[], int low, int high)
    {
        // code here
        // if(low == high)
        //     return arr;
        if(low<high)
        {    int m = partition(arr, low, high);
            quickSort(arr, low, m-1);
            quickSort(arr, m+1, high);
            // return arr;
        }
    }
    static int partition(int arr[], int low, int high)
    {
        // your code here
        int p = low;
   int q = high;
   int x = arr[p];
   int i = p;
 
   for (int j = p+1; j<=high; j++)
    {
        if(arr[j]<=x)
        {
            i++;
            int temp = arr[i];
            arr[i] = arr[j];
            arr[j] = temp;
        }
    }
        // swap(arr[i],arr[p]);
        int temp = arr[i];
        arr[i] = arr[p];
        arr[p] = temp;
        return i;
    }