2025-04-17 v. 9.2.8: added "3083. Existence of a Substring in a String and Its Reverse"

Author: fartem

README.md

@@ -455,6 +455,7 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 2549. Count Distinct Numbers on Board                              | [Link](https://leetcode.com/problems/count-distinct-numbers-on-board/)                              | [Link](./lib/easy/2549_count_distinct_numbers_on_board.rb)                              | [Link](./test/easy/test_2549_count_distinct_numbers_on_board.rb)                              |
 | 2652. Sum Multiples                                                | [Link](https://leetcode.com/problems/sum-multiples/)                                                | [Link](./lib/easy/2652_sum_multiples.rb)                                                | [Link](./test/easy/test_2652_sum_multiples.rb)                                                |
 | 2974. Minimum Number Game                                          | [Link](https://leetcode.com/problems/minimum-number-game/)                                          | [Link](./lib/easy/2974_minimum_number_game.rb)                                          | [Link](./test/easy/test_2974_minimum_number_game.rb)                                          |
+| 3083. Existence of a Substring in a String and Its Reverse         | [Link](https://leetcode.com/problems/existence-of-a-substring-in-a-string-and-its-reverse/)         | [Link](./lib/easy/3083_existence_of_a_substring_in_a_string_and_its_reverse.rb)         | [Link](./test/easy/test_3083_existence_of_a_substring_in_a_string_and_its_reverse.rb)         |
 | 3110. Score of a String                                            | [Link](https://leetcode.com/problems/score-of-a-string/)                                            | [Link](./lib/easy/3110_score_of_a_string.rb)                                            | [Link](./test/easy/test_3110_score_of_a_string.rb)                                            |
 | 3131. Find the Integer Added to Array I                            | [Link](https://leetcode.com/problems/find-the-integer-added-to-array-i/)                            | [Link](./lib/easy/3131_find_the_integer_added_to_array_i.rb)                            | [Link](./test/easy/test_3131_find_the_integer_added_to_array_i.rb)                            |
 | 3136. Valid Word                                                   | [Link](https://leetcode.com/problems/valid-word/)                                                   | [Link](./lib/easy/3136_valid_word.rb)                                                   | [Link](./test/easy/test_3136_valid_word.rb)                                                   |

lib/easy/3083_existence_of_a_substring_in_a_string_and_its_reverse.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/existence-of-a-substring-in-a-string-and-its-reverse/
+# @param {String} s
+# @return {Boolean}
+def is_substring_present(s)
+  return false if s.size < 2
+
+  rev = s.reverse
+  subs = []
+
+  (0..s.length - 2).each do |i|
+    subs << s[i, 2]
+  end
+
+  subs.any? { |sub| rev.include?(sub) }
+end

test/easy/test_3083_existence_of_a_substring_in_a_string_and_its_reverse.rb

@@ -0,0 +1,31 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/easy/3083_existence_of_a_substring_in_a_string_and_its_reverse'
+require 'minitest/autorun'
+
+class ExistenceOfASubstringInAStringAndItsReverseTest < ::Minitest::Test
+  def test_default_one
+    assert(
+      is_substring_present(
+        'leetcode'
+      )
+    )
+  end
+
+  def test_default_two
+    assert(
+      is_substring_present(
+        'abcba'
+      )
+    )
+  end
+
+  def test_default_three
+    assert(
+      !is_substring_present(
+        'abcd'
+      )
+    )
+  end
+end