Solution for Day 07

day_07/second.rb

@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+input = File.readlines('./test')
+
+map = input.map do |line|
+  bag = line[/\A(\w+\s\w+)/]
+  contains = line.scan(/(\d\s\w+\s\w+)/).flatten
+  Hash[bag, contains]
+end.inject :merge
+
+def count_bags(map, bag_color)
+  _, bags = map.find { |key, _| key.include? bag_color }
+  counts = bags.map do |bag|
+    _, mul, col = *bag.match(/(\d+) (\w+ \w+)/)
+    mul.to_i != 0 ? mul.to_i * count_bags(map, col) : 0
+  end
+
+  1 + (counts.inject(:+) || 0)
+end
+
+puts count_bags(map, 'shiny gold') - 1