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Sort Colors - Dutch Flag Partitioning Problem

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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.

def sortColors(self, nums):
    red, white, blue = 0, 0, len(nums)-1
    while white <= blue:
        if nums[white] == 0:
            nums[red], nums[white] = nums[white], nums[red]
            white += 1
            red += 1
        elif nums[white] == 1:
            white += 1
            nums[white], nums[blue] = nums[blue], nums[white]
            blue -= 1

Posted by Jamie Meyer 3 months ago

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