2025-03-14 v. 8.9.8: added "2095. Delete the Middle Node of a Linked List"

Author: fartem

README.md

@@ -731,6 +731,7 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 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)                                           |
 | 2091. Removing Minimum and Maximum From Array                                       | [Link](https://leetcode.com/problems/removing-minimum-and-maximum-from-array/)                                       | [Link](./lib/medium/2091_removing_minimum_and_maximum_from_array.rb)                                       | [Link](./test/medium/test_2091_removing_minimum_and_maximum_from_array.rb)                                       |
+| 2095. Delete the Middle Node of a Linked List                                       | [Link](https://leetcode.com/problems/delete-the-middle-node-of-a-linked-list/)                                       | [Link](./lib/medium/2095_delete_the_middle_node_of_a_linked_list.rb)                                       | [Link](./test/medium/test_2095_delete_the_middle_node_of_a_linked_list.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 = '8.9.7'
+  s.version = '8.9.8'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[README.md]
   s.executable = 'leetcode-ruby'

lib/medium/2095_delete_the_middle_node_of_a_linked_list.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/delete-the-middle-node-of-a-linked-list/
+# @param {ListNode} head
+# @return {ListNode}
+def delete_middle(head)
+  prev = nil
+  slow = head
+  fast = head
+
+  while fast&.next
+    prev = slow
+    slow = slow.next
+    fast = fast.next.next
+  end
+
+  return unless prev
+
+  prev.next = slow.next
+
+  head
+end

test/medium/test_2095_delete_the_middle_node_of_a_linked_list.rb

@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/common/linked_list'
+require_relative '../../lib/medium/2095_delete_the_middle_node_of_a_linked_list'
+require 'minitest/autorun'
+
+class DeleteTheMiddleNodeOfALinkedListTest < ::Minitest::Test
+  def test_default_one
+    assert(
+      ::ListNode.are_equals(
+        ::ListNode.from_array(
+          [1, 3, 4, 1, 2, 6]
+        ),
+        delete_middle(
+          ::ListNode.from_array(
+            [1, 3, 4, 7, 1, 2, 6]
+          )
+        )
+      )
+    )
+  end
+
+  def test_default_two
+    assert(
+      ::ListNode.are_equals(
+        ::ListNode.from_array(
+          [1, 2, 4]
+        ),
+        delete_middle(
+          ::ListNode.from_array(
+            [1, 2, 3, 4]
+          )
+        )
+      )
+    )
+  end
+
+  def test_default_three
+    assert(
+      ::ListNode.are_equals(
+        ::ListNode.from_array(
+          [2]
+        ),
+        delete_middle(
+          ::ListNode.from_array(
+            [2, 1]
+          )
+        )
+      )
+    )
+  end
+end