2025-01-01 v. 7.5.9: added "817. Linked List Components"

Author: fartem

README.md

@@ -623,3 +623,4 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 784. Letter Case Permutation                                    | [Link](https://leetcode.com/problems/letter-case-permutation/)                                    | [Link](./lib/medium/784_letter_case_permutation.rb)                                    | [Link](./test/medium/test_784_letter_case_permutation.rb)                                    |
 | 797. All Paths From Source to Target                            | [Link](https://leetcode.com/problems/all-paths-from-source-to-target/)                            | [Link](./lib/medium/797_all_paths_from_source_to_target.rb)                            | [Link](./test/medium/test_797_all_paths_from_source_to_target.rb)                            |
 | 814. Binary Tree Pruning                                        | [Link](https://leetcode.com/problems/binary-tree-pruning/)                                        | [Link](./lib/medium/814_binary_tree_pruning.rb)                                        | [Link](./test/medium/test_814_binary_tree_pruning.rb)                                        |
+| 817. Linked List Components                                     | [Link](https://leetcode.com/problems/linked-list-components/)                                     | [Link](./lib/medium/817_linked_list_components.rb)                                     | [Link](./test/medium/test_817_linked_list_components.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 = '7.5.8'
+  s.version = '7.5.9'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[README.md]
   s.executable = 'leetcode-ruby'

lib/medium/817_linked_list_components.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/linked-list-components/
+# @param {ListNode} head
+# @param {Integer[]} nums
+# @return {Integer}
+def num_components(head, nums)
+  values = nums.to_set
+  result = 0
+  is_connected = false
+
+  while head
+    if values.include?(head.val)
+      unless is_connected
+        is_connected = true
+        result += 1
+      end
+    else
+      is_connected = false
+    end
+
+    head = head.next
+  end
+
+  result
+end

test/medium/test_817_linked_list_components.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/common/linked_list'
+require_relative '../../lib/medium/817_linked_list_components'
+require 'minitest/autorun'
+
+class LinkedListComponentsTest < ::Minitest::Test
+  def test_default_one
+    assert_equal(
+      2,
+      num_components(
+        ::ListNode.from_array(
+          [0, 1, 2, 3]
+        ),
+        [0, 1, 3]
+      )
+    )
+  end
+
+  def test_default_two
+    assert_equal(
+      2,
+      num_components(
+        ::ListNode.from_array(
+          [0, 1, 2, 3, 4]
+        ),
+        [0, 3, 1, 4]
+      )
+    )
+  end
+end