189.3._rotate_array.rb

# frozen_string_literal: true

# https://leetcode.com/problems/rotate-array/

require_relative '../test_helper'

class Solution
  class << self
    def rotate(nums, k)
      k.times do |_|
        previous = nums[-1]

        nums.size.times do |i|
          temp = nums[i]
          nums[i] = previous
          previous = temp
        end
      end

      nums
    end
  end
end

class TestSolution < Minitest::Test
  def test_1
    nums = [1, 2, 3, 4, 5, 6, 7]
    k = 3
    output = [5, 6, 7, 1, 2, 3, 4]

    assert_equal output, Solution.rotate(nums, k)
  end

  def test_2
    nums = [-1, -100, 3, 99]
    k = 2
    output = [3, 99, -1, -100]

    assert_equal output, Solution.rotate(nums, k)
  end
end