Number reversal game: Difference between revisions

=={{header|Elixir}}==

{{trans|Erlang}}

<lang elixir>defmodule Number_reversal_game do

def start( n ) when n > 1 do

IO.puts "Usage: #{usage(n)}"

targets = Enum.to_list( 1..n )

jumbleds = Enum.shuffle(targets)

attempt = loop( targets, jumbleds, 0 )

IO.puts "Numbers sorted in #{attempt} atttempts"

end

defp loop( targets, targets, attempt ), do: attempt

defp loop( targets, jumbleds, attempt ) do

IO.inspect jumbleds

{n,_} = IO.gets("How many digits from the left to reverse? ") |> Integer.parse

loop( targets, Enum.reverse_slice(jumbleds, 0, n), attempt+1 )

end

defp usage(n), do: "Given a jumbled list of the numbers 1 to #{n} that are definitely not in ascending order, show the list then ask the player how many digits from the left to reverse. Reverse those digits, then ask again, until all the digits end up in ascending order."

end

Number_reversal_game.start( 9 )</lang>

{{out}}

<pre>

Usage: Given a jumbled list of the numbers 1 to 9 that are definitely not in ascending order, show the list then ask the player how many digits from the left to reverse. Reverse those digits, then ask again, until all he digits end up in ascending order.

[3, 9, 4, 7, 6, 5, 1, 2, 8]

How many digits from the left to reverse? 2

[9, 3, 4, 7, 6, 5, 1, 2, 8]

How many digits from the left to reverse? 9

[8, 2, 1, 5, 6, 7, 4, 3, 9]

How many digits from the left to reverse? 8

[3, 4, 7, 6, 5, 1, 2, 8, 9]

How many digits from the left to reverse? 3

[7, 4, 3, 6, 5, 1, 2, 8, 9]

How many digits from the left to reverse? 7

[2, 1, 5, 6, 3, 4, 7, 8, 9]

How many digits from the left to reverse? 4

[6, 5, 1, 2, 3, 4, 7, 8, 9]

How many digits from the left to reverse? 6

[4, 3, 2, 1, 5, 6, 7, 8, 9]

How many digits from the left to reverse? 4

Numbers sorted in 8 atttempts

</pre>