euler/e001.erl

27 lines
626 B
Erlang

% Add all the natural numbers below one thousand that are multiples of 3 or 5.
% If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.
% Find the sum of all the multiples of 3 or 5 below 1000.
-module(e001).
-export([
main/1
]).
sum(3) ->
0;
sum(Max) ->
N = Max - 1,
if
N rem 3 == 0 ->
A = N;
N rem 5 == 0 ->
A = N;
true ->
A = 0
end,
sum(N) + A.
main(_) ->
io:format("Sum of < 10: ~w~n", [sum(10)]),
io:format("Sum of < 1000: ~w~n", [sum(1000)]).