Sort Algorithm 2 - Quick Sort

def solution(nums):
    low, high = 0, len(nums)-1
    quickSort(nums,low,high)
    return nums

def quickSort(nums,low,high):
    if low < high:
        pivotpos = partition(nums,low,high)
        quickSort(nums,low,pivotpos-1)
        quickSort(nums,pivotpos+1,high)

def partition(nums,low,high):
    pivot = nums[low]
    while low < high:
        while low < high and nums[high] >= pivot:
            high -= 1
        nums[low] = nums[high]
        while low < high and nums[low] <= pivot:
            low += 1
        nums[high] = nums[low]
    nums[low] = pivot
    return low


if __name__ == "__main__":
    nums = [10, 17, 50, 7, 30, 24, 30, 45, 15, 5, 36, 21]
    print(solution(nums))

(1) avarage time cost: T(n) = O(nlogn)
(2) avarage time cost: S(n) = O(logn)
(3) in-place sort
(4) unstable
(5) best T(n)= O(nlogn), worst T(n) = O(nlogn)