Merge pull request #776 from fartem/438_Find_All_Anagrams_in_a_String

2024-11-19 v. 7.0.6: fixed "438. Find All Anagrams in a String"

Author: fartem

README.md

@@ -571,3 +571,4 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 429. N-ary Tree Level Order Traversal                           | [Link](https://leetcode.com/problems/n-ary-tree-level-order-traversal/)                           | [Link](./lib/medium/429_n_ary_tree_level_order_traversal.rb)                           | [Link](./test/medium/test_429_n_ary_tree_level_order_traversal.rb)                           |
 | 435. Non-overlapping Intervals                                  | [Link](https://leetcode.com/problems/non-overlapping-intervals/)                                  | [Link](./lib/medium/435_non_overlapping_intervals.rb)                                  | [Link](./test/medium/test_435_non_overlapping_intervals.rb)                                  |
 | 437. Path Sum III                                               | [Link](https://leetcode.com/problems/path-sum-iii/)                                               | [Link](./lib/medium/437_path_sum_iii.rb)                                               | [Link](./test/medium/test_437_path_sum_iii.rb)                                               |
+| 438. Find All Anagrams in a String                              | [Link](https://leetcode.com/problems/find-all-anagrams-in-a-string/)                              | [Link](./lib/medium/438_find_all_anagrams_in_a_string.rb)                              | [Link](./test/medium/test_438_find_all_anagrams_in_a_string.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 = '7.0.5'
+  s.version = '7.0.6'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[README.md]
   s.executable = 'leetcode-ruby'

lib/medium/438_find_all_anagrams_in_a_string.rb

@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/find-all-anagrams-in-a-string/
+# @param {String} s
+# @param {String} p
+# @return {Integer[]}
+def find_anagrams(s, p)
+  result = []
+  c_p = ::Array.new(128, 0)
+  p.each_byte { |b| c_p[b] += 1 }
+
+  c_s = ::Array.new(128, 0)
+  c = 0
+  (0...s.size).each do |i|
+    c_s[s[i].ord] += 1
+
+    next if (i - c + 1) < p.size
+
+    result << c if is_anagram?(c_s, c_p)
+
+    c_s[s[c].ord] -= 1
+    c += 1
+  end
+
+  result
+end
+
+private
+
+# @param {Integer[]} c_s
+# @param {Integer[]} c_p
+# @return {Boolean}
+def is_anagram?(c_s, c_p)
+  (0...c_s.size).each do |i|
+    return false unless c_s[i] == c_p[i]
+  end
+
+  true
+end

test/medium/test_438_find_all_anagrams_in_a_string.rb

@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/medium/438_find_all_anagrams_in_a_string'
+require 'minitest/autorun'
+
+class FindAllAnagramsInAStringTest < ::Minitest::Test
+  def test_default_one
+    assert_equal(
+      [0, 6],
+      find_anagrams(
+        'cbaebabacd',
+        'abc'
+      )
+    )
+  end
+
+  def test_default_two
+    assert_equal(
+      [0, 1, 2],
+      find_anagrams(
+        'abab',
+        'ab'
+      )
+    )
+  end
+end