mergeSort, quickSort, shellSort 的 python 实现

class Solution():
    def mergeSort(self, nums):
        def mergeSortR(nums):
            if len(nums) <= 1:
                return nums
            mid = len(nums)//2
            leftList = nums[:mid]
            rightList = nums[mid:]
            leftList = mergeSortR(leftList)
            rightList = mergeSortR(rightList)
            i, j = 0, 0
            newList = []
            while i < len(leftList) and j < len(rightList):
                if leftList[i] <= rightList[j]:
                    newList.append(leftList[i])
                    i += 1
                else:
                    newList.append(rightList[j])
                    j += 1
            if i == len(leftList):
                newList = newList + rightList[j:]
            else:
                newList = newList + leftList[i:]
            return newList
        return mergeSortR(nums)

if __name__ == '__main__':
    nums = [54, 26, 93, 17, 77, 31, 44, 55, 20]
    print(Solution().mergeSort(nums))
#################################################################################

class Solution():
    def __init__(self, nums):
        self.nums = nums

    def quickSort(self, start, end):
        if start+1 >= end:
            return
        index = self.partition(start, end)
        self.quickSort(start, index - 1)
        self.quickSort(index + 1, end)
        return self.nums

    def partition(self, start, end):
        ## how to write the pivot function!!
        pivot = self.nums[end]
        small_ind = start-1
        for i in range(start, end):
            if self.nums[i] < pivot:
                small_ind += 1
                if small_ind != i:
                    self.nums[i], self.nums[small_ind] = self.nums[small_ind], self.nums[i]
        small_ind += 1
        self.nums[end], self.nums[small_ind] = self.nums[small_ind], self.nums[end]
        return small_ind

if __name__ == '__main__':
    nums = [4, 3, 45, 2, 2, 35, 4]
    print(Solution(nums).quickSort(0, len(nums)-1))
###############################################################################################

class Solution():
    def __init__(self, nums, gaps):
        self.nums = nums
        self.gaps = gaps

    def shell_sort(self):
        # not the best way!!
        for gap in self.gaps:
            for g in range(gap):
                for i in range(g, len(self.nums), gap):
                    temp = self.nums[i]
                    for j in range(i, g-1, -gap):
                        if temp < self.nums[j-gap]:
                            self.nums[j] = self.nums[j-gap]
                        else:
                            break
                    self.nums[j] = temp
        return self.nums

    def shell_sort_official(self):
        for gap in self.gaps:
            for i in range(gap, len(self.nums)):
                temp = self.nums[i]
                for j in range(i, gap-1, -gap):
                    if self.nums[j-gap] > temp:
                        self.nums[j] = self.nums[j-gap]
                    else:
                        break
                self.nums[j] = temp
        return self.nums
if __name__ == '__main__':
    nums = [13,14, 94 ,33, 82, 25, 59, 94, 65, 23, 45, 27, 73, 25, 39, 10]
    gaps = [5, 3, 1]
    s = Solution(nums, gaps)
    print(s.shell_sort_official())