题解 | #数组移动# #颜色分类#

#coding:utf-8
#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
#
# 
# @param colors int整型一维数组 
# @return int整型一维数组
#
class Solution:
    def sortColor(self , colors ):
        # write code here
        n = len(colors)
        left = 0
        right = n - 1
        i = 0 #i是移动的指针
        while i <= right:
            #如果遇到2 放到最右边
            while i <= right and colors[i] == 2:
                tmp = colors[i]
                colors[i] = colors[right]
                colors[right] = tmp
                right -= 1
            #如果遇到0 放到左边
            if colors[i] == 0:
                tmp = colors[i]
                colors[i] = colors[left]
                colors[left] = tmp
                left += 1
            i += 1
        return colors