#! /usr/bin/env ruby
# https://repl.it/@sdrew/FogCreek-Application-Problem-Ruby

dict = ('a'..'z').to_a.tap { |arr| arr << '_' }.inject({}) { |memo, char| memo[char] = 0; memo }
data = File.read(File.join(__dir__, "data.txt"))

# METHOD A
# data.each_char do |char|
#   next if dict[char].nil?
#
#   dict[char] += 1
# end

# METHOD B
dict.keys.each { |char| dict[char] = data.count(char) }

sorted = dict.to_a.sort { |a, b| b[1] <=> a[1] }.inject([]) { |memo, arr| memo << arr.first; memo }
word = sorted.join('').split('_').first

puts word