Leetcode 0283. Move Zeroes

Given an integer array `nums`, move all `0`'s to the end of it while maintaining the relative order of the non-zero elements. Note that you must do this in-place without making a copy of the array.

Programming Skills I Easy

Description

Given an integer array nums, move all 0’s to the end of it while maintaining the relative order of the non-zero elements.

Note that you must do this in-place without making a copy of the array.

Example 1:

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

Example 2:

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

Constraints:

• 1 <= nums.length <= 10^4
• -2^31 <= nums[i] <= 2^31 - 1

Follow up:

• Could you minimize the total number of operations done?

Solution

class Solution:
    # Iteration
    # Time Complexity: BigO(N)
    # Space Complexity: BigO(N)
    def moveZeroes(self, nums: List[int]) -> None:
        """
        Do not return anything, modify nums in-place instead.
        """
        index = 0
        for i in nums:
            if i != 0:
                nums[index] = i
                index += 1

        for i in range(index, len(nums)):
            nums[i] = 0

/**
 * Do not return anything, modify nums in-place instead.
 * Iteration
 * Time Complexity: BigO(N)
 * Space Complexity: BigO(1)
 */
function moveZeroes(nums: number[]): void {
  let zeros = nums.filter((num) => num == 0).length;
  for (let i = 0; i < nums.length; i++) {
    if (nums[i] == 0 && zeros != 0) {
      let zero = nums.splice(i, 1)[0];
      nums.push(zero);
      zeros -= 1;
      i -= 1;
    }
  }
}