Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site rabbit.UUCP Path: utzoo!linus!security!genrad!decvax!harpo!eagle!allegra!alice!rabbit!ss From: ss@rabbit.UUCP Newsgroups: net.puzzle Subject: Re: "Looks simple" puzzle (spoiler) Message-ID: <2228@rabbit.UUCP> Date: Mon, 28-Nov-83 09:47:34 EST Article-I.D.: rabbit.2228 Posted: Mon Nov 28 09:47:34 1983 Date-Received: Tue, 29-Nov-83 06:06:54 EST References: <427@ihuxn.UUCP> Organization: AT&T Bell Laboratories, Murray Hill Lines: 39 ------------------------- The puzzle is to draw a line (please not on your terminal screen) WITHOUT LIFTING THE WRITING INSTRUMENT starting from any point not on an intersection of lines in such a way that every line segment is ONCE AND ONLY ONCE touched by your line. Every segment must be touched once. Look at the middle horizontal line: it has three segments, each of which must be touched once. You may pass through a line as long as yo do it only once. ----------------------------- Take the liberty of going OUT of large rectangle. Nothing in the problem statement prevents this. Here is one possible solution ------------------------------------------- ! /\_________!_/\ ! /\ ! ! / ! \ !/ -----------| !/ ! \ !\ ! | !\ ! \---\ ! \ ! | ! \ ! | ! \ ! | --|---------------------|-------|---------- | ! / ! / ---/ ! / !/ ! / / !/ !\ !/ / ! ! \ ! \ / ! ! \ ! \/ ! ------------------------------------------- Just one of the many that can be drawn. Still possible even if you count the middle horizontal line as four line segments. Note that it is also possible to make a closed curve without violating the problem statement. The apparant difficulty comes from the mental block set by the enclosing rectangle. Sharad Singhal. rabbit!ss