posted
Erlang & Project Euler
Just a quick and fairly simple post. I've been reading Programming Erlang over the last few days and decided tonight to have a quick play with the Project Euler problems (having never done them before). Here ~10 minutes work :)
%% Erlang Solution to Project Euler Problem #2
%% "Sum of all even primes under one million"
%% Written by Darcy Laycock
%% http://blog.ninjahideout.com/
-module(pe).
-compile(export_all).
start() ->
process(1000000).
process(Max) ->
io:format("Calculating All Even Fib. Under ~p~n", [Max]),
evenFactorialsUnder(1, 1, Max, 0).
printResults(0) ->
io:format("No Known Results.~n");
printResults(Results) ->
io:format("Found Result:~n~p~n", [Results]).
evenFactorialsUnder(A, B, Max, Acc) when A+B > Max ->
printResults(Acc);
evenFactorialsUnder(A, B, Max, Acc) ->
NewNum = A + B,
case NewNum rem 2 of
0 -> %% even
evenFactorialsUnder(NewNum, A, Max, Acc + NewNum);
1 -> %% odd
evenFactorialsUnder(NewNum, A, Max, Acc)
end.Edit: More of these coming tonight :) Simple but fun!
