Day5-75. Sort Colors

今日题目：75. Sort Colors(Medium)

Given an array nums with n objects colored red, white, or blue, sort them in-place so that objects of the same color are adjacent, with the colors in the order red, white, and blue.

We will use the integers 0, 1, and 2 to represent the color red, white, and blue, respectively.

You must solve this problem without using the library's sort function.

Example 1:
Input: nums = [2,0,2,1,1,0]
Output: [0,0,1,1,2,2]

Example 2:
Input: nums = [2,0,1]
Output: [0,1,2]

Example 3:
Input: nums = [0]
Output: [0]

Example 4:
Input: nums = [1]
Output: [1]

Constraints:

• n == nums.length
• 1 <= n <= 300
• nums[i] is 0, 1, or 2.

思路：

由头（i)和尾(j)开始两两比较，
j由後向前和i比较，
若j较i小，则ij交换
j全部比完後，则将向後移

My solution

class Solution:
    def sortColors(self, nums: List[int]) -> None:
        """
        Do not return anything, modify nums in-place instead.
        """
        n = len(nums)
        i=0
    
        for i in range(n):
            for j in range(n-1,i,-1):
                while j>i and nums[j] < nums[i]:
                    temp = nums[i]
                    nums[i] = nums[j]
                    nums[j] = temp

Result