Merge pull request #617 from fartem/2367_Number_of_Arithmetic_Triplets

2024-05-03 v. 5.6.0: added "2367. Number of Arithmetic Triplets"

Author: fartem

README.md

@@ -420,3 +420,4 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 2351. First Letter to Appear Twice                                 | [Link](https://leetcode.com/problems/first-letter-to-appear-twice/)                                 | [Link](./lib/easy/2351_first_letter_to_appear_twice.rb)                                 |
 | 2357. Make Array Zero by Subtracting Equal Amounts                 | [Link](https://leetcode.com/problems/make-array-zero-by-subtracting-equal-amounts/)                 | [Link](./lib/easy/2357_make_array_zero_by_subtracting_equal_amounts.rb)                 |
 | 2363. Merge Similar Items                                          | [Link](https://leetcode.com/problems/merge-similar-items/)                                          | [Link](./lib/easy/2363_merge_similar_items.rb)                                          |
+| 2367. Number of Arithmetic Triplets                                | [Link](https://leetcode.com/problems/number-of-arithmetic-triplets/)                                | [Link](./lib/easy/2367_number_of_arithmetic_triplets.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 = '5.5.9'
+  s.version = '5.6.0'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[bin/leetcode-ruby README.md LICENSE]
   s.executable = 'leetcode-ruby'

lib/easy/2367_number_of_arithmetic_triplets.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require 'set'
+
+# https://leetcode.com/problems/number-of-arithmetic-triplets/
+# @param {Integer[]} nums
+# @param {Integer} diff
+# @return {Integer}
+def arithmetic_triplets(nums, diff)
+  uniq = nums.to_set
+  nums.uniq.sum { |num| uniq.include?(num + diff) && uniq.include?(num + 2 * diff) ? 1 : 0 }
+end

test/easy/test_2367_number_of_arithmetic_triplets.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/easy/2367_number_of_arithmetic_triplets'
+require 'minitest/autorun'
+
+class NumberOfArithmeticTripletsTest < ::Minitest::Test
+  def test_default
+    assert_equal(2, arithmetic_triplets([0, 1, 4, 6, 7, 10], 3))
+    assert_equal(2, arithmetic_triplets([4, 5, 6, 7, 8, 9], 2))
+  end
+end