python 排序源码

以下是 Python 中常见的几种排序算法的源码实现：

1. 冒泡排序

def bubble_sort(nums):
    n = len(nums)
    for i in range(n):
        for j in range(n - i - 1):
            if nums[j] > nums[j+1]:
                nums[j], nums[j+1] = nums[j+1], nums[j]
    return nums

2. 选择排序

def selection_sort(nums):
    n = len(nums)
    for i in range(n):
        min_index = i
        for j in range(i+1, n):
            if nums[j] < nums[min_index]:
                min_index = j
        nums[i], nums[min_index] = nums[min_index], nums[i]
    return nums

3. 插入排序

def insertion_sort(nums):
    n = len(nums)
    for i in range(1, n):
        curr_val = nums[i]
        j = i - 1
        while j >= 0 and nums[j] > curr_val:
            nums[j+1] = nums[j]
            j -= 1
        nums[j+1] = curr_val
    return nums

4. 快速排序

def quick_sort(nums):
    if len(nums) <= 1:
        return nums
    pivot = nums[0]
    left = [x for x in nums[1:] if x < pivot]
    right = [x for x in nums[1:] if x >= pivot]
    return quick_sort(left) + [pivot] + quick_sort(right)

5. 归并排序

def merge_sort(nums):
    if len(nums) <= 1:
        return nums
    mid = len(nums) // 2
    left = merge_sort(nums[:mid])
    right = merge_sort(nums[mid:])
    return merge(left, right)

def merge(left, right):
    result = []
    i, j = 0, 0
    while i < len(left) and j < len(right):
        if left[i] < right[j]:
            result.append(left[i])
            i += 1
        else:
            result.append(right[j])
            j += 1
    result += left[i:]
    result += right[j:]
    return result