Day 4

Dependencies

• [2] XBZHQ672 Day 1 solution

Change contents

• file addition: day4.pl (----------)
  [2.7]
  + :- initialization(main).

  +

  + contains_duplicate([A|R]) :-

  + member(A,R).

  + contains_duplicate([_|R]) :-

  + contains_duplicate(R).

  +

  + read_lines(Fd,[W|L]) :-

  + read_string(Fd, "\n", "", Eof, W),

  + !,

  + ((Eof is -1, !, L = []); read_lines(Fd,L)).

  +

  + line_words(L,W) :- split_string(L," ", "", W).

  +

  + lines_words([],[]).

  + lines_words([A|R],[B|S]) :-

  + line_words(A,B),

  + lines_words(R,S).

  +

  + count_nodups([],0).

  + count_nodups([A|R],C) :-

  + (contains_duplicate(A); A = [""]),

  + !,

  + count_nodups(R,C).

  + count_nodups([_|R],C) :-

  + count_nodups(R,N),

  + ((nonvar(N), C is N + 1); (nonvar(C), N is C - 1)).

  +

  + main([Filename]) :-

  + open(Filename, read, Fd),

  + read_lines(Fd,L),

  + !,

  + lines_words(L,G),

  + count_nodups(G,C),

  + !,

  + writeln(C),

  + close(Fd),

  + halt.

  + main(_) :-

  + halt(1).