% https://open.kattis.com/problems/keytocrypto
% 1s
% 1.7 Easy
% 
% S E N D M O R E M O N K E Y S
% A C M S E N D M O R E M O N K
% S G Z V Q B U Q A F R W S L C

import util.

main => go.

% 205 chars
go =>
  [Code,Key] = read_file_lines(),
  Ds = [],
  foreach(I in 1..Code.len)
    D = chr(( (Code[I].ord-Key[I].ord) mod 26)+65),
    Ds := Ds ++ [D],
    Key := Key ++ [D]
  end,
  println(ds=Ds),
  nl.

% Recursive variant: 198 cgars
go2 => 
  [Code,Key] = read_file_lines(),
  d(Code,1,Key,[],S),
  println(S),
  nl.

d([],_,_,S,S).
d([C|Cs],I,Key,S0,[D|S]) :-
  D = chr(((C.ord-Key[I].ord) mod 26)+65),
  d(Cs,I+1,Key++[D],S0,S).

% First version
go3 =>
  [Code,Key] = read_file_lines(),
  println(code=Code),
  println(key=Key),

  Ds = [],
  Cs = [],
  foreach(I in 1..Code.len)
    println(i=I=Code[I]=Key[I]),
    C = Code[I].ord - 0'A, % '
    Cs := Cs ++ [Code[I]],
    K = Key[I].ord - 0'A, % '
    D = chr(( (C-K) mod 26) + 0'A), % '
    Ds := Ds ++ [D],
    println([c=Code[I],C,k=Key[I],K,d=D]),
    Key := Key ++ [D],
    println('ds '=Ds),
    println(key=Key),
    println('cs '=Cs),
    nl
  end,
  println(ds=Ds),
  println(key=Key),

  nl.