2024-09-23 v. 6.6.5: added "189. Rotate Array"

README.md

@@ -530,3 +530,4 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 173. Binary Search Tree Iterator                                | [Link](https://leetcode.com/problems/binary-search-tree-iterator/)                                | [Link](./lib/medium/173_binary_search_tree_iterator.rb)                                | [Link](./test/medium/test_173_binary_search_tree_iterator.rb)                                |
 | 179. Largest Number                                             | [Link](https://leetcode.com/problems/largest-number/)                                             | [Link](./lib/medium/179_largest_number.rb)                                             | [Link](./test/medium/test_179_largest_number.rb)                                             |
 | 187. Repeated DNA Sequences                                     | [Link](https://leetcode.com/problems/repeated-dna-sequences/)                                     | [Link](./lib/medium/187_repeated_dna_sequences.rb)                                     | [Link](./test/medium/test_187_repeated_dna_sequences.rb)                                     |
+| 189. Rotate Array                                               | [Link](https://leetcode.com/problems/rotate-array/)                                               | [Link](./lib/medium/189_rotate_array.rb)                                               | [Link](./test/medium/test_189_rotate_array.rb)                                               |

leetcode-ruby.gemspec

@@ -5,7 +5,7 @@ require 'English'
 ::Gem::Specification.new do |s|
   s.required_ruby_version = '>= 3.0'
   s.name = 'leetcode-ruby'
-  s.version = '6.6.4'
+  s.version = '6.6.5'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[README.md]
   s.executable = 'leetcode-ruby'

lib/medium/189_rotate_array.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/rotate-array/
+# @param {Integer[]} nums
+# @param {Integer} k
+# @return {Void} Do not return anything, modify nums in-place instead.
+def rotate189(nums, k)
+  k.times do
+    num = nums.pop
+    nums.unshift(num)
+  end
+end

test/medium/test_189_rotate_array.rb

@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/medium/189_rotate_array'
+require 'minitest/autorun'
+
+class RotateArrayTest < ::Minitest::Test
+  def test_default_one
+    arr = [1, 2, 3, 4, 5, 6, 7]
+    rotate189(arr, 3)
+
+    assert_equal(
+      [5, 6, 7, 1, 2, 3, 4],
+      arr
+    )
+  end
+
+  def test_default_two
+    arr = [-1, -100, 3, 99]
+    rotate189(arr, 2)
+
+    assert_equal(
+      [3, 99, -1, -100],
+      arr
+    )
+  end
+end