guess.rb

#!/usr/bin/env ruby

def main

  lower_bound = 1
  upper_bound = 100

  rand = Random.new
  current = rand.rand(lower_bound..upper_bound)
  previous_choices = []

  while true

    previous_choices.push(current)

    print "Is #{current} your number? [yes/no]: "

    break if gets =~ /^yes/

    print "Is it high or low? [high/low]: "

    answer = gets.strip

    if answer =~ /^high/
      upper_bound = current
    elsif answer =~ /^low/
      lower_bound = current
    end

    while previous_choices.include? current
      current = rand.rand(lower_bound..upper_bound)
    end

  end

  puts "Sweet!!!"

end

main()