RosettaCodeData/Task/FizzBuzz/Prolog/fizzbuzz-3.pro

21 lines
553 B
Prolog

% N /3? /5? V
fizzbuzz(_, yes, yes, 'FizzBuzz').
fizzbuzz(_, yes, no, 'Fizz').
fizzbuzz(_, no, yes, 'Buzz').
fizzbuzz(N, no, no, N).
% Unifies V with 'yes' if D divides evenly into N, 'no' otherwise.
divisible_by(N, D, V) :-
( 0 is N mod D -> V = yes
; V = no).
% Print 'Fizz', 'Buzz', 'FizzBuzz' or N as appropriate.
fizz_buzz_or_n(N) :-
divisible_by(N, 3, Fizz),
divisible_by(N, 5, Buzz),
fizzbuzz(N, Fizz, Buzz, FB),
format("~p -> ~p~n", [N, FB]).
main :-
foreach(between(1,100, N), fizz_buzz_or_n(N)).