happy.rb

def happy?(x)
  seen = []

  while !(seen.include?(x))
    seen << x
    x = x.to_s.chars.inject(0) { |sum, i| sum += (i.to_i * i.to_i) }
    #puts "iteration: #{x}\n"
    return true if x == 1
  end
  return false
end

start = Time.now
(1..10000).each do |i|
  puts "#{i} is " + (happy?(i) ? "" : "not ") + "happy\n"
end

puts "This program took #{Time.now - start} seconds"