LeetCode-in-All

283. Move Zeroes

Easy

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:

Follow up: Could you minimize the total number of operations done?

Solution

# @param {Integer[]} nums
# @return {Void} Do not return anything, modify nums in-place instead.
def move_zeroes(nums)
  first_zero = 0

  (0...nums.length).each do |i|
    if nums[i] != 0
      swap(first_zero, i, nums)
      first_zero += 1
    end
  end
end

private

def swap(index1, index2, numbers)
  val2 = numbers[index2]
  numbers[index2] = numbers[index1]
  numbers[index1] = val2
end