[quiz] [QUIZ #1] Solution by Stuart Sierra

[Stuart Sierra]

This is very similar to Joseph Abrahamson's solution.  The main 
difference is that I use separate databases for each part of the 
question: the initial set-up, the operation (addition or subtraction), 
and the final question.  I also got a little silly with the text of the 
questions.

This code can be extended to other operations by adding to the 
*operations* list and creating another *Xstrings* list, where X is the 
symbol name of the operation (e.g. +, -, *, ...).

My goal was to add enough "noise" to the question that it could not be 
solved by simple text calculators such as Google.  It's still pretty 
easy to crack this once you know the algorithm -- just scan the question 
string for numbers, add or subtract them, and you've got a 50% chance of 
getting the right answer.

Code attached.
-Stuart
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