anchor.diff:  -module(search).
  +
   -export([bfs/4, worker/2]).
  -% CAUTION: worker needs to be exported if it is to be called from the shell
  +%% CAUTION: worker needs to be exported if it is to be called from the shell
   
   -type state() :: _.
   -type environment() :: _.
  
positive.code: 		  lists:nth(1, Workers) ! {state, StateToSend},
  		  coordinator_outer(1, [], 0, Workers, Opts)
  	  end,
      % There are still messages left in the message queue - we need to wait for
      % the children to exit, then clean the mailbox just to be sure.
      wait_for_children(Opts#opts.workers),
      empty_mailbox(),
      process_flag(trap_exit, false),
  
negative.code:     end.
  
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  %% Parallel Run
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  -spec bfs_paral(environment(), state(), #opts{}) -> answer() | answer_S().
  