PROGRAM setranges4(output);
        { Written by: Mirsad Todorovac Nov 2001; copying by GPL.
        ------------------------------------------------------------
        Stresses setrange construction and adding; checks if there's
        all in SET what we've put in.
        lasts few seconds where I've tested it.}
CONST maxN = 255;
VAR   seta, setb, setc: SET OF 0..maxN;
      i, j, len, start, endr: Cardinal;
      failed: Boolean = false;

BEGIN
    FOR i:= 0 TO maxN DO
        IF ((i IN seta) OR (i IN setb) OR (i IN setc)) THEN
	    writeln('Failed: SET not initialized empty!');

    FOR len:= 1 TO maxN+1 DO
	BEGIN
	   FOR start:= 0 TO maxN-len+1 DO
	     BEGIN
	       endr := start+len-1;
	       {writeln('constr. range = ', start, ',', endr);}
	       setb := seta + [start .. endr];
	       FOR i:= 0 TO maxN DO
		 BEGIN
		   IF ((i >= start) AND (i <= endr) AND NOT (i IN setb)) THEN
                    IF (NOT failed) THEN
		     BEGIN
		      writeln('Failed: ', i,' inside range found NOT IN SET! ',
                               '[', start, '..', endr,']');
		       {It's sufficient for one example to fail to find a bug!}
		      failed := True;
                     END
		 END
             END
        END;
    IF (NOT failed) THEN
	writeln('OK');
								
END.