题解 | #颜色分类#

双指针

#coding:utf-8

class Solution:
    def sortColor(self , colors ):
        # write code here
        ptr_red = 0
        for i in range(len(colors)):
            if colors[i] == 0:
                colors[ptr_red], colors[i] = colors[i], colors[ptr_red]
                ptr_red += 1
        ptr_while = ptr_red
        for i in range(ptr_red, len(colors)):
            if colors[i] == 1:
                colors[ptr_while], colors[i] = colors[i], colors[ptr_while]
                ptr_while += 1
        return colors