Day one

1-1.rb

@@ -0,0 +1,14 @@
+#!/usr/bin/env ruby
+
+require "debug"
+
+input = File.readlines("1.input").map(&:split)
+
+first = input.map(&:first).compact.sort
+last = input.map(&:last).compact.sort
+
+result = first.map.with_index do |v, i|
+  (v.to_i - last[i].to_i).abs
+end.sum
+
+puts result

1-2.rb

@@ -0,0 +1,12 @@
+#!/usr/bin/env ruby
+
+input = File.readlines("1.input").map(&:split)
+
+first = input.map(&:first).compact
+last = input.map(&:last).compact
+
+result = first.map do |v|
+  v.to_i * last.select { _1.match?(v) }.size
+end.sum
+
+puts result