ProjectEuler14

def count input
  j = input.even? ? input/2 : 3*input + 1
  if $results[j].to_i==0; count j end
  $results[input] = $results[j] + 1
end

$results = { 1 => 1 }
(2..1000000).each { |i| count i }
puts $results.max_by{ |k,v| v }