Final Lecture

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Transcript Final Lecture

Final Lecture
Instructions in Exam
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ANSWER 2 QUESTIONS.
There will be a choice of 3 questions.
Each question will be in parts e.g. a, b, c.
You can see the marks awarded for correct
answers for each part.
Tips
• Before Exam, try past exam papers under exam conditions
• (e.g. turn off your phone and see if you can answer an exam paper
comfortably within the time).
• Read all of the questions.
• Sketch out your answers.
• Keep track of time e.g. spend about half the time on each question.
• You do not need to cheat (e.g. take in formula).
• Any reasoning you do with diagrams, I would do in pencil first,
• mistakes can be rubber out (and you can write in pen later).
• This is an easy exam so relax and do not worry.
• WRITE NEATLY
Time and Place
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04:30PM-06:30PM, 14/01/2008
Algorithmic Problem Solving
Year 2 CS; Year 2 CSM
SSB302
a≡b verse a=b
• With just 2 variable these are the same.
• With 3 or more variables they are different.
• a=b=c (read conjunctively) mean they are all the
same value
• just like integers or reals in maths.
• a≡b ≡c (read associately) i.e. a≡(b ≡c ) or as (a≡b)
≡c
• but actually these are both the same so we can
forget about the ()
• but a=b=c is not the same as a≡b ≡c
Knight and Knaves - again :(
• Knight tell truth, Knaves lie.
• (let 1 be Knights 0 be Knaves)
• If we ask A a Yes/No Question Q, the response to the
question will be true in 2 cases
• 1. the question is true and A is a Knight
• 2. the question is false and A is a Knave
• (in the other 2 cases it is false)
• We can summarize this as Q=A
• where Q is a yes/no question (i.e. a Boolean
proposition)
• and A is the Boolean proposition "A is a knight"
• Question to ask
• We want to find if A and B are the same type
(for example).
• The required response is A=B (i.e. A and B are
the same type)
• From the previous slide we know Q=A,
• therefore (Q=A)=(A =B),
• what does this simplify to?
Mex Numbers (again)
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draw a graph (random) and label with letters.
How is a state described.
Now label mex numbers
A mex number is the smallest natural number
not in the mex number of the successors.
Mex Numbers in Sum Games
• In a matchstick game we can remove 1 or 2
matches, label the diagram with a pattern.
• What it the mex number of the nth position?
• How do we play the sum game?
• How do we play a pair of matchstick games?
• How about a random graph and a the
component game from coursework 2.
Fuse Clocks – show fuseclock.ps file
• Given two fuses which burn for m and n,
create as many clocks as possible
• Clearly m and n need to be different.
Before the exam.
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Seminars.
If you have problem, mail me at
[email protected]
[email protected]
Good luck in Exam.