Quick Sort Algorithm Performed On C#

QuickSort.cs

public int[] QuickSort(int[] arr, int low, int high)
{
    if (low < high)
    {
        int pi = Partition(arr, low, high);
        QuickSort(arr, low, pi - 1);
        QuickSort(arr, pi + 1, high);
    }
    
    return arr;
}

private int Partition(int[] arr, int low, int high)
{
    int pivot = arr[high];
    int i = (low - 1);
    for (int j = low; j < high; j++)
    {
        if (arr[j] < pivot)
        {
            i++;
            int temp = arr[i];
            arr[i] = arr[j];
            arr[j] = temp;
        }
    }
    int temp1 = arr[i + 1];
    arr[i + 1] = arr[high];
    arr[high] = temp1;
    return i + 1;
}