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Challenge 2

Click for Hint Harry has built a system to encipher simple messages and it looks like he has left it lying around next to his report to Meg (affine cipher section on tools page). If you are stuck, why not try using it to see if you can crack this one by brute force?
Once you have done that you will know something about Part B and you can have a go at cracking it yourself. If you need extra help, take a look at the Beginner’s Guide again, it is full of useful ideas!

Part A: SNOOPING AROUND

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Part B:A CHANGE OF COURSE

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