Merge pull request #679 from fartem/59_Spiral_Matrix_II

2024-07-19 v. 6.2.2: added "59. Spiral Matrix II"

Author: fartem

README.md

@@ -487,3 +487,4 @@ Profile on LeetCode: [fartem](https://leetcode.com/fartem/).
 | 55. Jump Game                                               | [Link](https://leetcode.com/problems/jump-game/)                                               | [Link](./lib/medium/55_jump_game.rb)                                               |
 | 56. Merge Intervals                                         | [Link](https://leetcode.com/problems/merge-intervals/)                                         | [Link](./lib/medium/56_merge_intervals.rb)                                         |
 | 57. Insert Interval                                         | [Link](https://leetcode.com/problems/insert-interval/)                                         | [Link](./lib/medium/57_insert_interval.rb)                                         |
+| 59. Spiral Matrix II                                        | [Link](https://leetcode.com/problems/spiral-matrix-ii/)                                        | [Link](./lib/medium/59_spiral_matrix_ii.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 = '6.2.1'
+  s.version = '6.2.2'
   s.license = 'MIT'
   s.files = ::Dir['lib/**/*.rb'] + %w[bin/leetcode-ruby README.md LICENSE]
   s.executable = 'leetcode-ruby'

lib/medium/59_spiral_matrix_ii.rb

@@ -0,0 +1,71 @@
+# frozen_string_literal: true
+
+# https://leetcode.com/problems/spiral-matrix-ii/
+# @param {Integer} n
+# @return {Integer[][]}
+def generate_matrix(n)
+  i = 0
+  j = 0
+  up = 0
+  right = 1
+  left = 2
+  down = 4
+
+  up_side = 0
+  right_side = n
+  left_side = -1
+  down_side = n
+  direction = right
+  value = 0
+  result = ::Array.new(n) { ::Array.new(n) { nil } }
+
+  while value < n * n
+    if direction == up
+      while i > up_side
+        value += 1
+        result[i][j] = value
+        i -= 1
+      end
+
+      i += 1
+      j += 1
+      up_side += 1
+      direction = right
+    elsif direction == right
+      while j < right_side
+        value += 1
+        result[i][j] = value
+        j += 1
+      end
+
+      i += 1
+      j -= 1
+      right_side -= 1
+      direction = down
+    elsif direction == left
+      while j > left_side
+        value += 1
+        result[i][j] = value
+        j -= 1
+      end
+
+      i -= 1
+      j += 1
+      left_side += 1
+      direction = up
+    else
+      while i < down_side
+        value += 1
+        result[i][j] = value
+        i += 1
+      end
+
+      i -= 1
+      j -= 1
+      down_side -= 1
+      direction = left
+    end
+  end
+
+  result
+end

test/medium/test_59_spiral_matrix_ii.rb

@@ -0,0 +1,12 @@
+# frozen_string_literal: true
+
+require_relative '../test_helper'
+require_relative '../../lib/medium/59_spiral_matrix_ii'
+require 'minitest/autorun'
+
+class SpiralMatrixIITest < ::Minitest::Test
+  def test_default
+    assert_equal([[1, 2, 3], [8, 9, 4], [7, 6, 5]], generate_matrix(3))
+    assert_equal([[1]], generate_matrix(1))
+  end
+end