common.cr

@@ -20,25 +20,3 @@ class Rectangle
     end
   end
 end
-
-class String
-  def select(&block)
-    String.build do |s|
-      each_char do |c|
-        s << c if yield c
-      end
-    end
-  end
-
-  def select!(&block)
-    i = 0
-    s = size
-    while i < s
-      if yield [i]
-        i += 1
-      else
-        s -= 1
-      end
-    end
-  end
-end

day5.cr

@@ -1,34 +0,0 @@
-require "./common.cr"
-
-lines = File.read("day5_input").split("\n")
-
-struct Char
-  def inverse?(other)
-    return (other != self) && (other.downcase == self.downcase)
-  end
-end
-
-def react(string)
-  stack = [] of Char
-
-  string.each_char do |char|
-    last_char = stack.last?
-    if !last_char || !last_char.inverse? char
-      stack << char
-    else
-      stack.pop
-    end
-  end
-
-  return stack
-end
-
-puts react(lines[0]).size
-
-pairs = {} of Tuple(Char, Char) => Int32
-('a'..'z').to_a.zip(('A'..'Z').to_a).each do |pair|
-  new_string = lines[0].select { |c| c != pair[0] && c != pair[1] }
-  pairs[pair] = react(new_string).size
-end
-
-puts pairs.values.min