LeetCode（283. 移动零）

问题描述

给定一个数组 nums，编写一个函数将所有 0 移动到数组的末尾，同时保持非零元素的相对顺序。

示例:

输入: [0,1,0,3,12]
输出: [1,3,12,0,0]

说明:

1. 必须在原数组上操作，不能拷贝额外的数组。
2. 尽量减少操作次数。

解决方案

1.最快的原地置换

class Solution:
    def moveZeroes(self, nums):
        """
        :type nums: List[int]
        :rtype: void Do not return anything, modify nums in-place instead.
        """
        zero = 0
        for i in range(len(nums)):
            if not nums[i] == 0 and zero <= i:
                nums[i], nums[zero] = nums[zero], nums[i]
                zero += 1

2.使用remove+append

class Solution:
    def moveZeroes(self, nums):
        """
        :type nums: List[int]
        :rtype: void Do not return anything, modify nums in-place instead.
        """
        count = 0
        while 0 in nums:
            nums.remove(0)
            count+=1
        for i in range(count):
            nums.append(0)

3.先覆盖，再写入0

class Solution:
    def moveZeroes(self, nums):
        """
        :type nums: List[int]
        :rtype: void Do not return anything, modify nums in-place instead.
        """
        count = 0
        for i in range(0, len(nums)):
            if (nums[i] != 0):
                nums[count] = nums[i]
                count += 1
        for j in range(count, len(nums)):
            nums[j] = 0