Merge pull request #673 from fartem/49_Group_Anagrams

2024-07-16 v. 6.1.6: added "49. Group Anagrams"

Author: fartem

README.md

@@ -481,3 +481,4 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 43. Multiply Strings                                        | [Link](https://leetcode.com/problems/multiply-strings/)                                        | [Link](./lib/medium/43_multiply_strings.rb)                                        |
 | 46. Permutations                                            | [Link](https://leetcode.com/problems/permutations/)                                            | [Link](./lib/medium/46_permutations.rb)                                            |
 | 48. Rotate Image                                            | [Link](https://leetcode.com/problems/rotate-image/)                                            | [Link](./lib/medium/48_rotate_image.rb)                                            |
+| 49. Group Anagrams                                          | [Link](https://leetcode.com/problems/group-anagrams/)                                          | [Link](./lib/medium/49_group_anagrams.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 = '6.1.5'
+  s.version = '6.1.6'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[bin/leetcode-ruby README.md LICENSE]
   s.executable = 'leetcode-ruby'

lib/medium/49_group_anagrams.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: false
+
+# https://leetcode.com/problems/group-anagrams/
+# @param {String[]} strs
+# @return {String[][]}
+def group_anagrams(strs)
+  values = {}
+  strs.each do |str|
+    key = ::Array.new(str.length, '')
+    (0...str.length).each { |i| key[i] = str[i] }
+
+    k = key.sort.join
+
+    if values.key?(k)
+      values[k] << str
+    else
+      values[k] = [str]
+    end
+  end
+
+  values.values
+end

test/medium/test_49_group_anagrams.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/medium/49_group_anagrams'
+require 'minitest/autorun'
+
+class GroupAnagramsTest < ::Minitest::Test
+  def test_default
+    assert_equal(
+      [%w[eat tea ate], %w[tan nat], ['bat']],
+      group_anagrams(%w[eat tea tan ate nat bat])
+    )
+    assert_equal([['']], group_anagrams(['']))
+    assert_equal([['a']], group_anagrams(['a']))
+  end
+end