{ Copyright (C) 1981 by Bell Laboratories, Inc., and Whitesmiths Ltd. }
{ addstr -- put  c  in  outset[j]  if it fits,  increment  j }
function addstr(c : character; var outset : string;
		var j : integer; maxset : integer) : boolean;
begin
	if (j > maxset) then 
		addstr := false
	else begin
		outset[j] := c;
		j := j + 1;
		addstr := true
	end
end;