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.

class Solution:
    def sortColors(self, nums: List[int]) -> None:
        """
        Do not return anything, modify nums in-place instead.
        """
        zero = 0
        one = 0
        two = len(nums) - 1

        while one <= two:
            if nums[one] == 0:
                nums[zero], nums[one] = nums[one], nums[zero]
                zero += 1
                one += 1
            elif nums[one] == 1:
                one += 1
            elif nums[one] == 2:
                nums[two], nums[one] = nums[one], nums[two]
                two -= 1