From: Stuart Holden Date: 2006-05-05T22:52:29+09:00 Subject: Re: [QUIZ] Bracket Packing (#78) Quick question about the phrase 'occasionally missing off a bracket'. Is it possible to have lost more than one braket missing from the string, or will it be a case of 0..1 brackets missing? I assume just one. If it is possible to have more than one bracket missing, you could never trust what the program was saying, even when the string was valid. Ie, [{(B),(B)}] -> [(B),(B)] - Stu -----Original Message----- From: Ruby Quiz [mailto:james@grayproductions.net] Sent: 05 May 2006 12:47 To: ruby-talk ML Subject: [QUIZ] Bracket Packing (#78) The three rules of Ruby Quiz: 1. Please do not post any solutions or spoiler discussion for this quiz until 48 hours have passed from the time on this message. 2. Support Ruby Quiz by submitting ideas as often as you can: http://www.rubyquiz.com/ 3. Enjoy! Suggestion: A [QUIZ] in the subject of emails about the problem helps everyone on Ruby Talk follow the discussion. Please reply to the original quiz message, if you can. -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= -=-=-=-= by Ross Bamford The BigCo Bracket Company, one of the world's largest suppliers of brackets, hinges and fittings, has lately been experiencing problems in it's manufacturing division, with a large number or brackets lost or broken in transit owing to faulty packaging at the end of the line. Investigations into the cause of the problem have led engineers to an ancient COBOL program controlling the packaging machinery. This program is responsible for selecting the type of packaging a given bracket should be shipped in, based on input from an array of sensors on the production line. It then sends a description of the package to the packager itself, which packs the bracket and sends it on to shipping. The description is a simple text string, made up of brackets with the following format: (B) - Bracket in a soft wrapping [B] - Bracket in a cardboard box {B} - Bracket in a wooden box Often, brackets have multiple layers of packaging for protection, for example: {(B)} - Soft-wrapped bracket in a wooden box [{B}] - Wooden-boxed bracket with cardboard outer [{(B)}{(B)(B)}] - Wooden boxed single and double bracket packs with soft inner wrap, in cardboard outer. Now, the problem is that this venerable program has for some reason begun to output malformed packaging descriptions, occasionally missing off a bracket, for example: [{(B}{(B)(B)}] or: {(B)}{(B)(B)}] After a fruitless search for someone with the skills to fix this problem, the engineers changed tack and called you in to fix the problem from the outside. What needs to be done? ====================== Basically, the plan is to insert another computer between the controller and the packer, upon which will run your program. The engineers can handle the integration with their systems - they just need you to write a slick bit of Ruby code to validate the packaging descriptions as they're passed in. You've been given two choices: * Check the description, and return exitcode indicating it's okay (0) or bad (1). If correct, you should also print the description to stdout. If it's bad, the system can then force the controller to try again. * Fix the description, if possible, and print it to stdout. The system will then pass the fixed code to the packer.

This Email may contain confidential and privileged information and is intended for the use of the addressee(s) only. If you are not the intended recipient please notify the sender and delete the Email from your system. It should not be transmitted to any other person without the consent of the sender. Additional important notifications regarding Email transmissions from and to members of Baring Asset Management can be accessed at http://www.barings.com/email/index.hcst