Time for an 2014 update…

This commit is contained in:
Ingy döt Net 2014-01-17 05:32:22 +00:00
parent 372c577f83
commit 09687c4926
2520 changed files with 34227 additions and 7318 deletions

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-module( digital_root ).
-export( [task/0] ).
task() ->
Ns = [N || N <- [627615, 39390, 588225, 393900588225]],
Persistances = [persistance_root(X) || X <- Ns],
[io:fwrite("~p has additive persistence ~p and digital root of ~p~n", [X, Y, Z]) || {X, {Y, Z}} <- lists:zip(Ns, Persistances)].
persistance_root( X ) -> persistance_root( sum_digits:sum_digits(X), 1 ).
persistance_root( X, N ) when X < 10 -> {N, X};
persistance_root( X, N ) -> persistance_root( sum_digits:sum_digits(X), N + 1 ).