[leetcode] 283 move zero

Given an array nums, Write a function that will 0 Move to end of array , While maintaining the relative order of non-zero elements .

Please note that , You must operate on the array in place without copying it .

Example 1:

Input : nums = [0,1,0,3,12]
Output : [1,3,12,0,0]

Example 2:

Input : nums = [0]
Output : [0]

Tips :

• 1 <= nums.length <= 104
• -231 <= nums[i] <= 231 - 1

# Stupid method 
class Solution(object):
    def moveZeroes(self, nums):
        n = len(nums)
        for i in range(n):
            if nums[n-i-1]==0:
                tmp = nums.pop(n-i-1)
                nums.append(tmp)

# Double pointer , Speed pointer , Fast pointer fast traversal sequence value , Encountered a non-zero number covering the slow pointer position 
class Solution(object):
    def moveZeroes(self, nums):
        length = len(nums)
        slow = 0
        for fast in range(length):
            if nums[fast]:
                nums[slow] = nums[fast]
                slow+=1
        nums[slow:]=(length-slow)*[0]