Solve Josephus Problem Using Erlang

Josephus（約瑟夫）問題的數學方法

%%%----------------------------------------------------------------%%% @author Genesislive <genesislive@126.com>%%% [https://]%%% @copyright 2013 %%% @doc josephus problem%%% @end%%%-----------------------------------------------------------------module(josephus). -export([josephus_it/2, josephus/2]). %%-----------------------------------------------------------------%% @doc solve josephus problem%%fun(1) = 0,一個人；%%fun(n) = (fun(n - 1) + m) % n,  n個人%% @spec josephus_it(N, M) -> integer()%% where%%  N:integer() number of people%%  M:integer() mth people%% @end%%-----------------------------------------------------------------josephus_it(1, _) -> 0;josephus_it(N, M) ->(josephus_it(N - 1, M) + M) rem N. %%-----------------------------------------------------------------%% @doc%% @end%%-----------------------------------------------------------------josephus(N, M) ->lists:foldl(fun(I, S) ->   % io:format("~p~n", [((S + M) rem I)]),   ((S + M) rem I)end, 0, lists:seq(2, N)).