As we enter the final rounds of the competition there is a lot to play for. Hopefully this week will slow some of you down Muhaha!! [<- Harry's evil laugh]
On the other hand 'tis the season to be jolly so, in the spirit of giving joy (if not to all mankind, at least to some of you), each of the following 8 teams will win a cheque for £25. As always we will be in touch by email to the address you gave us when registering, so do please check it and get back to us promptly so we can process your award.
To everyone else, (for two more rounds at least) there is always next week. Good luck,
Harry
Winners of the Part 6A Prizes:
Dean Hope, Jacob Maximilian, Wolfgang Williams, Katie Roberts, Rebecca Breen and Laura Downey from Ellesmere Port Catholic High School
Ahalya, Isobel and Isabel from City of London School for Girls
Stephen Falconer, Keiran Rooney and Tom Bryant from Havant College
Lauren and Alice from Malet Lambert School
Tom Blackie, James Gaskin, Hannah Brooks, Jessie Crane, Ryan Wiliams, Fred Shortridge and Amy Richards from The Plume School
Charlotte Muehlschlegel, Daisy Watson, Kousha Wrigley, Elena Guss, Tarazona and Nika Bienko from Simon Langton Girls' Grammar School
Euan from Magdalen College School, Oxford
Samuel, Eilidh andPhoebe from Yateley
How did you get on with the Vigenere cipher this week? It is a particularly tricky cipher when you first meet it since standard frequency analysis doesn't help much. Since the cipher alphabet changes from letter to letter you need to analyse frequencies of longer strings - digraphs and so on - and the best way to tackle it is to figure out the repeat length by calculating the index of coincidence. I'll leave you to look that up. The first real attack on that cipher was by Babbage, inventor of the difference engine and father of computing. You can see examples of his work at the science Museum in Kensington. A Polish cryptographer is also credited with the same method of attack (Babbage-Kasiski deciphering), though Babbage was definitely first. On the other hand the Poles were the first to make a serious break on the Enigma cipher and without their input Bletchley would have had a much harder job in the war.
Each of the following 8 teams will win a cheque for £25 for their entry to Challenge 5A. We will be in touch by email to the address you gave us when registering, so do please check it and get back to us promptly so we can process your award.
To everyone else, there is always next week. Good luck,
Harry
Winners of the Part 5A Prizes:
Nixon S Joe L Peter S Grzegorz P from Cardinal Newman College
Amy Beswick Emma Williams from Fairfield High School For Girls
Roddis' Angels from Queen's Elizabeth's High School
Graz H Langer from Runshaw College
Norm Yeung from Magdalen College school
Nina Simister from Dorothy Stringer
Thomas Bodley, Humayun Khan, Praveenan Mathew and Danial Sheikh from St. Joseph's College
Miranda and Jessie from City of London School for Girls
Now it is really getting tough. 644 teams submitted a correct entry for Challenge 4B, down from the 1,000 that succeeded in 1B but we still have a way to go so don't give up yet. Hut 1 is catching up with Hut 2 on the Hut Leader Board, but Huts 3 and 4 really do need to work at Challenge 5A to get back into the game. Meanwhile each of the following 8 teams will win a cheque for £25 for their efforts on Challenge 4A. We will be in touch by email to the address you gave us when registering, so do please check it and get back to us promptly so we can process your award.
Hope you enjoy this week's Challenge. All the best, Harry
Winners of the Part 4A Prizes:
- Mannat, Annis and Miranda from City of London School for Girls
- Rubix from Fulford Secondary School
- Rachael Young, Courtney Thompson, Emma Fox and Ben Farnworth from Cardinal Newman College
- Rose from Tonbridge Grammar School
- Sam Pritchard and Maxim Cooper from Wells Cathedral School
- Emma Bussell, Jake Perrett James Gard Meghna Dwyer from Gryphon School
- Alex from St Edwards Oxford
- Enigmatica from The King's School Canterbury
Well, that was the first week that really counted for the part B championship and the first week of the Hut Challenge. A lot of you found 3B hard, but many of you cracked it and should feel proud of yourselves. The following 8 lucky teams will win a cheque for £25 for their entry to part 3A. We will be in touch by email to the address you gave us when registering, so do please check it and get back to us promptly so we can process your award.
To everyone else, there is always next week. Good luck,
Harry
Winners of the Part 3A Prizes:
asdfghjkl; from Haybridge High School and Sixth Form
Anindita from City of London School for Girls
Cat Brown from Farnborough Sixth Form College
Leah, Nicole, Maarukh, Manraj, Osman and Qasim from The Langley Academy
Gemma Wignall from Westholme School
Molly, Becky, Rexhina and Erin from Stewards Academy
Lewis Hicks, Ben Crocket and Callum Looker from Redruth school
Lily & Zak from Dulverton Middle School
During a speech at Bletchley Park on Thursday 18th October, the Foreign Secretary William Hague 
announced three joint initiatives between the Foreign and Commonwealth Office and GCHQ.
Alongside funding for the restoration of Bletchley Park and the announcement of the new apprenticeship scheme for intelligence officers, William Hague formally launched this year's National Cipher Challenge at the event. I accompanied the Head of Mathematics of the University of Southampton to the event as guests of the director of GCHQ and had the pleasure of meeting a number of Bletchley veterans as well as current members of the intelligence services.
As a result the competion has made the press internationally, who are fascinated by the "spy kids" angle and the "school for spooks" so you are all now famous as apprentice spies and you should all feel very proud of Å·our achievements.
All the best, Harry
