Merlin Morgenstern wrote: > Hello everybody, > > I am having trouble finding a logic for following problem: > > Should be true if: > page = 1 OR page = 3, but it should also be true if page = 2 OR page = 3 > > The result should never contain 1 AND 2 in the same time. > > This obviously does not work: > (page = 1 OR page = 3) OR (page = 2 OR page = 3) > > This also does not work: > (page = 1 OR page = 3 AND page != 2) OR (page = 2 OR page = 3 AND page > != 1) > > Has somebody an idea how to solve this? > > Thank you in advance for any help! > > Merlin Surely what you need is xor (exclusive-or) I can't believe a programmer has never heard of that! (page==1 XOR page==2) AND page==3 -- Peter Ford phone: 01580 893333 Developer fax: 01580 893399 Justcroft International Ltd., Staplehurst, Kent -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php