2024-08-13 v. 6.4.6: added "120. Triangle"

Author: fartem

README.md

@@ -511,3 +511,4 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 114. Flatten Binary Tree to Linked List                         | [Link](https://leetcode.com/problems/flatten-binary-tree-to-linked-list/)                         | [Link](./lib/medium/114_flatten_binary_tree_to_linked_list.rb)                         |
 | 116. Populating Next Right Pointers in Each Node                | [Link](https://leetcode.com/problems/populating-next-right-pointers-in-each-node/)                | [Link](./lib/medium/116_populating_next_right_pointers_in_each_node.rb)                |
 | 117. Populating Next Right Pointers in Each Node II             | [Link](https://leetcode.com/problems/populating-next-right-pointers-in-each-node-ii/)             | [Link](./lib/medium/117_populating_next_right_pointers_in_each_node_ii.rb)             |
+| 120. Triangle                                                   | [Link](https://leetcode.com/problems/triangle/)                                                   | [Link](./lib/medium/120_triangle.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 = '6.4.5'
+  s.version = '6.4.6'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[README.md]
   s.executable = 'leetcode-ruby'

lib/medium/120_triangle.rb

@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/triangle/
+# @param {Integer[][]} triangle
+# @return {Integer}
+def minimum_total(triangle)
+  return triangle.first.first if triangle.size == 1
+
+  result = ::Array.new(triangle.size + 1, 0)
+  (0..(triangle.size - 1)).reverse_each do |i|
+    curr_size = triangle[i].size
+    (0...curr_size).each do |j|
+      result[j] = [result[j], result[j + 1]].min + triangle[i][j]
+    end
+  end
+
+  result.first
+end

test/medium/test_120_triangle.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/medium/120_triangle'
+require 'minitest/autorun'
+
+class TriangleTest < ::Minitest::Test
+  def test_default
+    assert_equal(11, minimum_total([[2], [3, 4], [6, 5, 7], [4, 1, 8, 3]]))
+    assert_equal(-10, minimum_total([[-10]]))
+  end
+end