1. 图解

2. 代码

from typing import List


class Solution:
    # 冒泡排序
    def bubble_sort(self, nums: List[int]) -> List[int]:
        n = len(nums)
        for i in range(n):
            for j in range(1, n - i):
                if nums[j - 1] > nums[j]:
                    nums[j - 1], nums[j] = nums[j], nums[j - 1]
        return nums

    # 每次用第一个和后面的作对比
    def bubble_sort_2(self, nums: List[int]) -> List[int]:
        n = len(nums)
        for i in range(n - 1):
            for j in range(i + 1, n):
                if nums[i] > nums[j]:
                    nums[i], nums[j] = nums[j], nums[i]
        return nums


if __name__ == "__main__":
    s = Solution()
    nums = [3,4,2,1,3,4,5,67,19]
    a = s.bubble_sort(nums)
    print(a)