Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 (Tek) 9/26/83; site tekchips.UUCP Path: utzoo!watmath!clyde!burl!hou3c!hocda!houxm!mhuxl!ulysses!unc!mcnc!decvax!ucbvax!ucbcad!tektronix!tekchips!stevev From: stevev@tekchips.UUCP Newsgroups: net.math Subject: Re: Need help finding algorithm Message-ID: <839@tekchips.UUCP> Date: Mon, 4-Jun-84 12:31:36 EDT Article-I.D.: tekchips.839 Posted: Mon Jun 4 12:31:36 1984 Date-Received: Wed, 6-Jun-84 06:36:56 EDT Organization: Tektronix, Beaverton OR Lines: 27 > I was asked to create a schedule for opponent play in >a league. There were 22 members in the league and they >wanted each player to play every other player once, with >no player playing more than once a week. That meant that >it would be a 21 week schedule with 11 two person games a >week. ... A simple schedule for 2n players in 2n-1 weeks may be found by placing the players names in two rows of n entries. The players in the same column play each other the first week. For the next week, rotate all players (say clockwise) except the player in the top/left position (who stays where he is). For the week after that, perform the same rotation, etc. A five-week six-player schedule, for example is as follows: Week 1: Week 2: Week 3: Week 4: Week 5: 1 2 3 1 6 2 1 5 6 1 4 5 1 3 4 6 5 4 5 4 3 4 3 2 3 2 6 2 6 5 The rotation is such that 2 is always in the position that 3 was in the previous week, 3 in 4's last position ... 6 in 2's last position, etc. For the first week, 1 plays 6, 2 plays 5, 3 plays 4; the second week 1 plays 5, 6 plays 4 and 2 plays 3, etc. Steve Vegdahl Tektronix, Inc. Beaverton, OR