Given an array nums, write a function to move all 0's to the end of it while maintaining the relative order of the non-zero elements.
For example, given nums = [0, 1, 0, 3, 12], after calling your function, nums should be [1, 3, 12, 0, 0].
Note:
- You must do this in-place without making a copy of the array.
- Minimize the total number of operations
把数组中的0全放在数组尾部，非0数组保持原顺序
思路：用一个i表示最近一个0点，for遍历中遇到非0点与num[i]交换
class Solution:
def moveZeroes(self, nums):
"""
:type nums: List[int]
:rtype: void Do not return anything, modify nums in-place instead.
"""
i = 0
for x in range(len(nums)):
if(nums[x] != 0):
nums[x], nums[i] = nums[i], nums[x]
i += 1
return nums
leetcode提供的解
思路：将非0元素全交换在前，最后对数组用0补全
class Solution:
def moveZeroes(self, nums):
"""
:type nums: List[int]
:rtype: void Do not return anything, modify nums in-place instead.
"""
k = 0
for x in nums:
if x != 0:
nums[k] = x
k += 1
nums[k:] = [0] * (len(nums) - k)
return nums