Move Zeroes

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.

Example:

`Input: [0,1,0,3,12]Output: [1,3,12,0,0]`

Note:

1. You must do this in-place without making a copy of the array.
2. Minimize the total number of operations.

Hint #1

In-place means we should not be allocating any space for extra array. But we are allowed to modify the existing array. However, as a first step, try coming up with a solution that makes use of additional space. For this problem as well, first apply the idea discussed using an additional array and the in-place solution will pop up eventually.

Hint #2

A two-pointer approach could be helpful here. The idea would be to have one pointer for iterating the array and another pointer that just works on the non-zero elements of the array.

Solution:

`class Solution:    def moveZeroes(self, nums: List[int]) -> None:                n = len(nums)        count = 0                for i in range(n):            if nums[i] != 0:                nums[count] = nums[i] # move all the non-zero elements to the front                count += 1                        while count < n:            nums[count] = 0            count += 1        return nums`