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October 27, 2005
Winners for Challenge 4
Congratulations to this week's lucky winners for Challenge 4 part A:
Sarah Humphreys from Manchester High School for Girls, Manchester.
Jazz, Hanna and Fishy, the 3.141592 team from The Mount School, North Yorkshire, York, North Yorkshire.
George Schofield , the from Brighton College, Brighton.
Emma Burrows, (EmmaGHS) from Guildford High School, Surrey, Guildford, Surrey.
Amy Leung and Sumayya Shahid, team SA from The Latymer School, London.
Tom and Ted, Tom's Titans from High School for Girls, Gloucester.
Isabelle Pan, Danielle Avital, Maya Patel, Laura Mclean and Nicole Drake, (MLIND) from The Henrietta Barnett School, London,
Josh Williams from Richard Lander School, Truro.
James Cook Rohit, Emanuele and James Piper, the 8Acers from Northolt High School, Northolt, Middlesex.
David Christopher Ragusa 1 from The London Oratory School.
Posted by Harry at 09:02 PM | Comments (25)
Scoring for Challenge 5
Maximum points this week: 40 for any correct entry received today
After that the points drop by 1 every 8 hours. Any questions? Good luck,
Posted by Harry at 03:27 PM | Comments (19)
Hint and explanation of rule 9
When we proces your entry we remove all the non-alphabetic characters and put it in lower case so if you submit a solution with the string H*a1R /r(y) we read it as harry. We then compare this to our master solution which we have treated the same. However sometimes the ciphertext contains some of these deleted characters. It is not a good idea to delete them and then try to decipher the text as they can be useful in helping with the deciphering, and you don't need to delete them to submit as we will do that for you. So unless you are told otherwise you should leave them in. No doubt this will trigger a flurry of requests for clarification, and I will collect them and post a response here when it is clear where any confusion lies. All the best,
Posted by Harry at 01:00 PM
October 24, 2005
Computers and stuff
As I said earler, there is a great discussion of programming languages going on here, but I just wanted to remark that, while computers certainly can speed up code breaking, most of the ciphers we use in the competition don't need clever programmes to break them. You could tackle them using pencil and paper if you had to, though you can speed up the process by using a word processor or spreadsheet. The last challenge in the competition really would be tricky to tackle that way, but by the time we are done giving hints, clues and extra info you should even be able to crack that one without writing any code, so don't despair if you don't know how to get started.
On the other hand you shouldn't be put off trying something new. Even writing an Excel macro to replace the cipher alphabet with the plaintext alphabet can give you a real buzz when it works, and of you have time to play with a perl script or a simple visual basic programme it may give you confidence to try something more adventurous next time.
Posted by Harry at 10:57 PM | Comments (11)
HINT FOR CHALLENGE 4B
By now it's no secret that Challenge 4B is in Morse. We used our new auto-transcriber to read the stream of Morse signals and encode them as 0's and 1's. Each 0 represents a dash, and each 1 represents a dot.
Turns out there are a lot of unfamiliar Morse characters aside from the usual 26 letters of the alphabet. Look around online and you should find the ones you need. By the way take a look at the layout. Seems the Soviets are using a grouping in sixes. That breaks down just once, and that is no accident.
By the way don't forget to look for cribs, they can make life a LOT easier.
Good luck,
Posted by Harry at 09:34 PM | Comments (9)
October 22, 2005
Programming languages
In case you've missed it there is a good discussion of programming languages going on in the comments on the site. Take a look around.
Posted by Harry at 07:04 PM | Comments (30)
.... and Winners for Challenge 3
Congratulations to more beneficiaries of our digital sorting hat. You have been awarded the standard £25 prize for Challenge 3:
Gurbur Singh Dhaliwal,from Handsworth Grammar School, Birmingham, West Midlands
Sean O'Caroll, The Cipher Cloak from The London Oratory School, London,
Alaeze, Wow! I Survived! Thanks To My Bulletproof Vest from The London Oratory School, London,
Katie Cockburn, Gemma George, Katie Meadon and Isabelle Groves, the Pinkys from Woking High School, Woking, Surrey
Henry Carruthers, Jenny Roberts, Jenny Clay and Lee Samuels, Phoenix_ASHS from Archbishop Sancroft High School, Harleston, Norfolk
Freya Ferguson, Michelle Parker and Sophie Wilcox, the Black Swallows from Oxford High School GDST, Oxford
Tom Halpin and Conor Churchill, the The Wombles from Bishop Wordsworth's Grammar School, Salisbury, Wiltshire
Richard Allen, Jacob Chhapi, Hasan Ali and David Souter, White Lightning from Leicester Grammar School, Leicestershire, Leicester
David Comley, Sam and Alex Cobb and Sam Nicholson, Team Alpha from Robert May's School, Hook, Hampshire
Ben Campbell, from Handsworth Grammar School, Birmingham
As before, please get in touch so we can arrange to send you the cheque. We need a payee and the address of your school. If you can tell us the name of your headteacher as well that would be great. Thanks,
Posted by Harry at 04:39 PM
Winners for Challenge 2
Congratulations to the following who have been pulled out of an electronic hat to receive prizes for part 2 of the Challenge:
Jon and Charlie, The Cheese Graters from Blatchington Mill School and Sixth Form College, Hove, East Sussex
Cameron McHendry, Angus Bracks, Rebecca Hutchinson, Emma Inkster and Alex Sloan, The Porty Maths Machines from Portobello High School, Edinburgh,
Joe Williams, the Team Young 1 from Tunbridge Wells Grammar School for Boys, Tunbridge Wells, Kent
Ou Jeilyn Sun Yoon, Grace Sze Chui, Michelle Ziling Ou, MISSJ from The Mount School, York
Jason Bell, Try Try Again from The Nelson Thomlinson School, Wigton, Cumbria
Alex Radon, Matt Pykett and Dave Southey, the Pint Of Milk from Trinity Catholic School, Nottingham, Nottinghamshire
Kimberley Parsons, the Fluffy Waffle from Woodlands Community School, Southampton, Hampshire
Philip Burton and Thomas Mileham, the Philtom from Yeovil College, Yeovil, Somerset
Christian Butcher, Miles Martin, Robert Danvers and James Shorter, the Insane from Formby High School, Liverpool, Merseyside
Jospeh Razavi, Jonathan Gamble and Andrew, Several More Cheesey Crackers from Painsley Catholic High School, Stoke-on-Trent, Staffordshire
Each team listed gets £25. If you are on this list please contact us to tell us who you want the cheque made out to and to confirm the school postal address.
Posted by Harry at 04:36 PM
October 21, 2005
Hints
wow. I have held back so many comments in the last 18 hours that my head hurts from reading them all. I will try to release some of them over the next few days, but don't want to give too much away too soon, and they contain so many good hints. Keep trying, and keep watching the Boat's Log for more help later on. All the best,
Posted by Harry at 02:39 PM | Comments (2)
October 20, 2005
Is there a mistake in Challenge 4B?
Errrr. No there isn't. Maybe you need to study Samuel's code a bit more. I'll be a bit less cryptic later. All the best,
Posted by Harry at 05:17 PM | Comments (40)
Timing for Challenge 4
The points for Challenge 4B go as follows:
Any correct solution by midnight today (Thursday 20th October) 25 points
After that the points decrease by one every six hours, so 24 points for a correct solution before 6am on Friday 21st October, 23 for a solution between 6am and midday and so on. Hope that is clear. We also hope that Challenge B slows you right down this week! Good luck,
Posted by Harry at 03:43 PM | Comments (11)
October 18, 2005
HINTS FOR CHALLENGES 3B and 4B
Sorry we've been quiet, I've been travelling. I'd tell you where i've been, but then I'd have to kill you. Anyway, It looks to me like the cipher in message 3B might be one of those keyword ciphers, so it is monoalphabetic and just a matter of doing the frequency analysis again. Good luck with it.
Have to figure the Soviets might try something sneakier some time. I have a new toy to transcribe the Soviet Morse Code as it comes in, so you might see something a little different on Thursday.
All the best,
Posted by Harry at 07:28 PM
Prizes for week 2
Sorry we haven't published the prizewinners for week 2. There will be an announcement soon. All the best,
Posted by Harry at 01:09 AM | Comments (10)
October 13, 2005
Timing
Its the age old problem of when we should publish the Challenge. This time it is triggered by the remark that one of the Challenges will be published during half term and not everyone has broadband. This shouldn't be a major problem since most people do have access to a local library with internet access. Check it out. Your local librarian will be delighted at the increase in business. All the best,
Posted by Harry at 02:02 PM | Comments (15)
October 12, 2005
Timing for Challenge 3
Lots of requests for info about the scoring for Challenge 3. This time we will use half day intervals, with a slight twist. You'll get 13 points for an entry on Thursday evening, 12 points for an entry between midnight and midday on Friday, and so on down to 1 point for an entry between midday and midnight on Wednesday. Hope that is clear.
Posted by Harry at 08:23 PM | Comments (5)
October 11, 2005
HINT 2 FOR CHALLENGE 2B
Frequency analysis gives a good way to attack Challenge 2B but as many of you have discovered, used on its own it does leave a certain ambiguity in that some letters appear so rarely (maybe only once) that it is hard to determine what they stand for among the possible rarely used plaintext characters.
The best way to disambiguate the text is to figure out what sort of cipher the Soviets are using for the message. It isn't just random. You know from your succesful efforts to crack it that it must be some kind of simple monoalphabetic substitution, but it isn't a Caesear shift, so what could it be? I won't tell you which, but it is likely to be either a keyword cipher or perhaps an affine shift as these are the two simplest examples. Look them up! Good luck,
Posted by Harry at 03:07 PM | Comments (4)
Honours Board
You may notice that some of the details on the honours board are currently wrong or out of date. We have had some team changes, some teams accidentally entered the wrong school information, and in some cases the "Other members of the team" field on the registration form was filled in to include the team captain, so on the honours board you see "Joe Bloggs, Joe Bloggs and Steve Globbs" instead of "Joe Bloggs and Steve Globbs". You can help us get this right by updating your registration info using the form at http://www.cipher.maths.soton.ac.uk/cipherreg/regedit.phtml. Please don't leave it until Thursday as we will run the programme to generate the next Honours Board by then and that too will show the wrong information about you. I'll give another hint about Challenge 2B in my next post. All the best,
Posted by Harry at 02:57 PM | Comments (0)
October 09, 2005
CHALLENGE 2B HINT
Stuck on 2B? The first hurdle is the morse code. You can tackle this by hand or using a word processor to replace each morse sequence by the appropriate sequence of letters. This will give you a standard ciphertext. Unfortunately this one doesn't appear to be a Caesar shift (that's because it isn't one) so you need to work a bit harder to crack it. If you check the frequency with which letters appear in the ciphertext you should see that one appears most often so that probably represents e, that gives you somewhere to start. Look for a common three letter sequence - this probably represents the word "the", carrying on like this gives a way to crack open the cipher. In fact this cipher is still a fairly simple one, and we wrote about it in the Teachers' Pack which you can download from this site at this url. Take a look, it is full of useful tips. Good luck,
Posted by Harry at 06:18 PM | Comments (11)
October 07, 2005
WINNERS FOR CHALLENGE 1 PRIZES
We are still waiting to hear from the winners confirming their details, but I promised to publish the names by today, so here they are. If you have won you should have had an email. Please get back to me asap so we can send you your prize. Each of the following teams wins £25. Congratulations. And congratualtions to all of you taking part. We have more participants than ever. Keep up the good work.
The winners are:
Fusties (Michael Jevon) from Queen Mary's Grammar School, Walsall
Kirsti Biggs from South Wilts Grammar School for Girls, Wiltshire
Weapons Of Math Destruction from Bridgewater Middle School, Hertfordshire (Alex Hutto, Ben Rodgers and Alex Ball)
Daleks Together (Richard Hall and Geoffrey Hall) from Pate's Grammar School, Gloucestershire
Jose Mirza from Brighton College
The Circumnavigator (Emily Kenyon) from St Anne's Convent School, Southampton
Luczabeth (Lucy, Beth, Zabel) from City of London School for Girls
Googly Geometry (Greg Jordan, Jonny Williams and Michael Whalley) from Swavesey Village College, Cambridgeshire
The Pirates (Tom Mellor, Omar Al-harthy, Ryan Shutt, Lawrence Schofield, Gary James, Joe Pender, Sam Dennis and Imogene Rutherford) from Mounts Bay School, Penzance
The3musketeers (Harry Inman, Tom Warner, Tommy Lwin) from Bishop Wordsworth's Grammar School, Wiltshire
Posted by Harry at 10:48 PM | Comments (10)
October 06, 2005
Can't resubmit?
To try to protect us against multiple submissions we have recoded the site so that when you submit a solution it prevents you from resubmitting without closing the browser window first. In some cases opening a new browser window doesn't seem to clear the obstruction. You can try closing the browser programme and relaunching it, or emptying the browser cache. If that doesn't work you might try rebooting your computer though that is a bit extreme. In a very few cases it may be caused by a proxy service cacheing pages and delivering the cached version. We have designed the pages to discourage this but have no control over it, sorry. If you have any worries do get in touch. All the best,
Posted by Harry at 09:34 PM
Challenge 1 prizes etc
We will announce the winners of the Challenge 1 part A lottery tonight or tomorrow (just to keep you wondering). How are you getting on with Challenge 2? Someone asked if they should leave the dashes in their solution. You can, it doesn't matter. Remember maximum points for solutions received tonight, then they go down by a point per day 'til next Wednesday. All the best,
Posted by Harry at 06:26 PM | Comments (36)
October 03, 2005
48 hours for Challenge 1, scoring for Challenge 2
You have 48 hours left to submit your solution to Challenge 1. The next challenge gets published at 4pm on Thursday, but there is no need to rush to download it. The points scheme for Challenge 2 will award seven points for any solution we receive Thursday, 6 points for any solution we receive on Friday and so on so you can take your time.
Posted by Harry at 11:15 PM | Comments (24)