https://leetcode-cn.com/problems/move-zeroes/ (opens new window) 需要注意的点

1. python 没有自加，https://www.runoob.com/note/24457 (opens new window)， https://www.runoob.com/python/python-func-id.html (opens new window)
2. 该题用到了快慢指针

class Solution(object):
    def moveZeroes(self, nums):
        """
        :type nums: List[int]
        :rtype: None Do not return anything, modify nums in-place instead.
        """
        index = self.removeElement(nums, 0)
        # 将数组index后面的元素赋0
        while index < len(nums):
            nums[index] = 0
            index += 1
        return nums


        
    def removeElement(self, nums, val):
        """
            快慢指针， 快指针总是在增加，
            慢指针只有在符合条件的时候才增加
        """

        fast = 0
        slow = 0
        while fast < len(nums):
            # slow 符合条件才增加，该题条件是 当fast != val
            if nums[fast] != val:
                nums[slow] = nums[fast]
                slow += 1
            
            # fast 总是增加
            fast += 1

        return slow

class Solution(object):
    def moveZeroes(self, nums):
        """
        :type nums: List[int]
        :rtype: None Do not return anything, modify nums in-place instead.
        """
        # index = self.removeElement(nums, 0)
        fast = 0
        slow = 0
        while fast < len(nums):
            # slow 符合条件才增加，该题条件是 当fast != val
            if nums[fast] != 0:
                nums[slow] = nums[fast]
                slow += 1
            
            # fast 总是增加
            fast += 1

        while slow < len(nums):
            nums[slow] = 0
            slow += 1
        return nums


        
    def removeElement(self, nums, val):
        """
            快慢指针， 快指针总是在增加，
            慢指针只有在符合条件的时候才增加
        """
        pass