Move Zeros

In this task, I worked on rearranging an array so that all the zeroes are moved to the end, while keeping the order of the non-zero elements the same.

What I Did

I created a function called moveZeroes that takes an array and shifts all zero values to the end without changing the order of the other elements.

For example:
Input: [0, 1, 0, 3, 12]
Output: [1, 3, 12, 0, 0]

How I Solved It

To solve this problem, I used a variable called insert_pos to keep track of where the next non-zero element should go.

First, I went through the array:

• If the element is not zero, I placed it at the insert_pos and moved the position forward

After placing all non-zero elements, I filled the remaining positions in the array with zeroes.

Code

def moveZeroes(nums):
    insert_pos = 0
    for num in nums:
        if num != 0:
            nums[insert_pos] = num
            insert_pos += 1
    while insert_pos < len(nums):
        nums[insert_pos] = 0
        insert_pos += 1

nums = [0, 1, 0, 3, 12]
print("Before:", nums)
moveZeroes(nums)
print("After:", nums)

How It Works

The function first shifts all non-zero elements to the front of the array while keeping their order unchanged. Then it fills the remaining positions with zeroes.

This way, the operation is done in a single pass without using extra space, making it efficient and easy to understand.