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+# 75. Sort Colors
+
+"""
+given an array 'nums' with 'n' objects coloured red, white, or blue, sort
+them in place so that objects of the same colour are adjacent with the
+colours in the order red, white and blue. we will use the integer 0,1,2 to
+represent the colour red, white, and blue respecitvely. you must solve this
+problem without the library's sort function.
+"""
+
+
+class Solution(object):
+ def sortColors(self, nums):
+ """
+ :type nums: List[int]
+ :rtype: None Do not return anything, modify nums in-place instead.
+ """
+ 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
+ else:
+ nums[white], nums[blue] = nums[blue], nums[white]
+ blue -= 1
+
+
+if __name__ == "__main__":
+ obj = Solution()
+ n1 = [2, 0, 2, 1, 1, 0]
+ n2 = [2, 0, 1]
+ obj.sortColors(n1)
+ obj.sortColors(n2)
+ print(n1)
+ print(n2)