rearrange.rb

require 'json'

artists = {}

Dir.glob('charts/*').select do |f|
  contents = File.read(f)
  chart = JSON.load(contents)
  chart.each.with_index do |song, i|

    unless artists.has_key?(song['artist'])
      artists[song['artist']] = {}
    end

    unless artists[song['artist']].has_key?(song['title'])
      reduced = {
        :title => song['title'],
        :artist => song['artist'],
        :positions => []
      }
      artists[song['artist']]['title'] = reduced
    end
    artists[song['artist']]['title'][:positions] << [f.split('/')[1], i]
  end
end

JSON.dump(artists, File.open("./reduced.json", "w"))

Haskell implementation ~2hrs in, no luck so far. Starting on rust implementation.