%%prettify
{{{
defmodule GuessingGame do
 # tell user our guess
 # "yes" game over
 # "bigger" -> bigger( low, high )
 # "smaller" -> smaller( low, high )
 # anything else -> tell user to enter a valid response

 def guess(a, b) when a > b, do: guess(b, a) # guard, matches only, when a > b
 
 def guess(low, high) do
   answer = IO.gets "Hmm... maybe you're thinking of #{mid(low, high)}?\n"
   case String.trim(answer) do
     "bigger" -> bigger(low, high)
     "smaller" -> smaller(low, high)
     "yes" -> "I knew I could guess your number!"
     _ ->
       IO.puts ~s(Type "bigger", "smaller" or "yes")
guess(low, high)
   end
 end
 
 def mid( low, high) do
   div low + high, 2
 end

 def bigger(low, high) do
   new_low = min( high, mid(low, high) + 1)
   guess(new_low, high)
 end

 def smaller(low, high) do
   new_high = max(low, mid(low, high) - 1)
   guess(low, new_high)
 end  
end
}}}
/%


[{Tag funktionaleProgrammierung}]