2025-03-14 v. 8.9.6: added "2074. Reverse Nodes in Even Length Groups"

Author: fartem

README.md

@@ -729,6 +729,7 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 2023. Number of Pairs of Strings With Concatenation Equal to Target                 | [Link](https://leetcode.com/problems/number-of-pairs-of-strings-with-concatenation-equal-to-target/)                 | [Link](./lib/medium/2023_number_of_pairs_of_strings_with_concatenation_equal_to_target.rb)                 | [Link](./test/medium/test_2023_number_of_pairs_of_strings_with_concatenation_equal_to_target.rb)                 |
 | 2058. Find the Minimum and Maximum Number of Nodes Between Critical Points          | [Link](https://leetcode.com/problems/find-the-minimum-and-maximum-number-of-nodes-between-critical-points/)          | [Link](./lib/medium/2058_find_the_minimum_and_maximum_number_of_nodes_between_critical_points.rb)          | [Link](./test/medium/test_2058_find_the_minimum_and_maximum_number_of_nodes_between_critical_points.rb)          |
 | 2063. Vowels of All Substrings                                                      | [Link](https://leetcode.com/problems/vowels-of-all-substrings/)                                                      | [Link](./lib/medium/2063_vowels_of_all_substrings.rb)                                                      | [Link](./test/medium/test_2063_vowels_of_all_substrings.rb)                                                      |
+| 2074. Reverse Nodes in Even Length Groups                                           | [Link](https://leetcode.com/problems/reverse-nodes-in-even-length-groups/)                                           | [Link](./lib/medium/2074_reverse_nodes_in_even_length_groups.rb)                                           | [Link](./test/medium/test_2074_reverse_nodes_in_even_length_groups.rb)                                           |
 | 2116. Check if a Parentheses String Can Be Valid                                    | [Link](https://leetcode.com/problems/check-if-a-parentheses-string-can-be-valid/)                                    | [Link](./lib/medium/2116_check_if_a_parentheses_string_can_be_valid.rb)                                    | [Link](./test/medium/test_2116_check_if_a_parentheses_string_can_be_valid.rb)                                    |
 | 2425. Bitwise XOR of All Pairings                                                   | [Link](https://leetcode.com/problems/bitwise-xor-of-all-pairings/)                                                   | [Link](./lib/medium/2425_bitwise_xor_of_all_pairings.rb)                                                   | [Link](./test/medium/test_2425_bitwise_xor_of_all_pairings.rb)                                                   |
 | 2429. Minimize XOR                                                                  | [Link](https://leetcode.com/problems/minimize-xor/)                                                                  | [Link](./lib/medium/2429_minimize_xor.rb)                                                                  | [Link](./test/medium/test_2429_minimize_xor.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 = '8.9.5'
+  s.version = '8.9.6'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[README.md]
   s.executable = 'leetcode-ruby'

lib/medium/2074_reverse_nodes_in_even_length_groups.rb

@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/reverse-nodes-in-even-length-groups/
+# @param {ListNode} head
+# @return {ListNode}
+def reverse_even_length_groups(head)
+  nodes = []
+  p = head
+
+  while p
+    nodes << p
+    p = p.next
+  end
+
+  counter = 1
+  size = nodes.size
+  index = 0
+
+  while size.positive?
+    count = [counter, size].min
+
+    if count.even?
+      upper_limit = count + index - 1
+      i = index
+      j = 0
+
+      while j < count / 2
+        a = nodes[i]
+        b = nodes[upper_limit - j]
+        temp = a.val
+        a.val = b.val
+        b.val = temp
+
+        i += 1
+        j += 1
+      end
+    end
+
+    size -= counter
+    index += counter
+    counter += 1
+  end
+
+  head
+end

test/medium/test_2074_reverse_nodes_in_even_length_groups.rb

@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/common/linked_list'
+require_relative '../../lib/medium/2074_reverse_nodes_in_even_length_groups'
+require 'minitest/autorun'
+
+class ReverseNodesInEvenLengthGroupsTest < ::Minitest::Test
+  def test_default_one
+    assert(
+      ::ListNode.are_equals(
+        ::ListNode.from_array(
+          [5, 6, 2, 3, 9, 1, 4, 8, 3, 7]
+        ),
+        reverse_even_length_groups(
+          ::ListNode.from_array(
+            [5, 2, 6, 3, 9, 1, 7, 3, 8, 4]
+          )
+        )
+      )
+    )
+  end
+
+  def test_default_two
+    assert(
+      ::ListNode.are_equals(
+        ::ListNode.from_array(
+          [1, 0, 1, 6]
+        ),
+        reverse_even_length_groups(
+          ::ListNode.from_array(
+            [1, 1, 0, 6]
+          )
+        )
+      )
+    )
+  end
+
+  def test_default_three
+    assert(
+      ::ListNode.are_equals(
+        ::ListNode.from_array(
+          [1, 0, 1, 5, 6]
+        ),
+        reverse_even_length_groups(
+          ::ListNode.from_array(
+            [1, 1, 0, 6, 5]
+          )
+        )
+      )
+    )
+  end
+end