cs0004 16.1 exam revsion %282010-2011%29

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29

http://slidepdf.com/reader/full/cs0004-161-exam-revsion-282010-201129 1/25

Click to edit Master subtitle style

Algorithms and theirApplications

CS2004 2010-2011Dr Stephen Swift

16.1 Exam Revision

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29


CS2004 Exam RevisionCS2004 Exam Revision 2Slide 2

Introduction

n This lecture is a revision lecture forthe exam for this module

n The exam is on Tuesday 10th May at

2pmnIn this lecture we are going to cover:

n The assessment

n The format of the examnExam topicsnSome example questions

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29



Assessment

n The overall structure for theassessment is as follows:

n

50% Coursework (done)n10% Laboratory work sheets(done)n

40% Exam (pending)

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29



Exam

nA two hour examn The location should now be available

n This will consist of:n A multiple choice part A worth 40%n An essay-type question part B worth

60%

nAll questions should beattempted

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29



What to Revise – Part 1

n The exam will cover thetheoretical aspects of the modulen

There will be no programmingneedednNo questions on Java or Eclipse

n

However you may need tounderstand and/or write somepseudo code

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29




n Topics could include (not restrictedto):

nAlgorithmic conceptsnWhat is an algorithm, a program, etc…

n Time Complexity and Asymptotic NotationnT (n) and O(n)

nData structuresnStacks, lists, arrays, queues, etc…

nSorting AlgorithmsnBubblesort, Quicksort, etc…

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29

http://slidepdf.com/reader/full/cs0004-161-exam-revsion-282010-201129 7/25 CS2004 Exam RevisionCS2004 Exam Revision 7Slide 7


n Topics could include (not restrictedto):

nGraph Traversal AlgorithmsnDepth First, Breadth First, A*, MST, etc…

nSearchnSearch, Search Space, Fitness, Parameter optimisation, etc...

nHeuristic Search MethodsnHC, SHC, RRHC, SA, ILS, etc...

nEvolutionary Computation and Other MethodsnGenetic Algorithms, PSO, ACO, etc...

nApplicationsnBin Packing, Data Clustering, TSP, etc...

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29


Exam – Part A – Part 1

nMultiple choice questions(40%)

n

Choose an answer from a list of optionsn20 questions of 2 marks eachn

Spend about 2 minutes perquestionnUse the multiple choice answersheet

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29


Exam – Part A – Part 2

nGood strategies for multiplechoice questions:

nRead through all of the questions firstnAnswer the ones that you know firstnDo NOT spend too much time on asingle question

nOften ruling out answers can reducethe options down to a fewnDo not leave any blank!

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29


Exam – Part B – Part 1

nEssay type questionsn4 questions of 15 marksn

Spend approximately 15 minutesper questionnWrite your answers in the answerbook

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29


Exam – Part B – Part 2

nGood strategies for essay typequestions:

nRead through all of the questions firstnAnswer the ones that you know firstnDo NOT spend too much time on asingle question

nSketching a draft answer can help inlaying out complex answersnCross out anything you do not wantmarked

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29


Example Multiple Choice –Part 1

nWhat is pseudo code?na) A Java programnb) A programming languageindependent description of analgorithmnc) The intermediate code

produced by the Java compilernd) An algorithmic description of acomputer program

ne) None of the above

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29



nAlgorithm A runs in time complexity O(n2),algorithm B in O(n3) and algorithm C inO(n2). Which of the following statements istrue?

na) Algorithm B is always faster than C

nb) Algorithm A and C are the same

nc) Algorithm A is slower than Algorithm B

n

d) Algorithm A and C are asymptoticallysimilar in performance

ne) None of the above

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29



nWhich of the following data structureswould be appropriate for storing a list of names and addresses?

na) A stack

nb) A queue

nc) An array

nd) A linked list

n

e) It depends on the application

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29



nWhich of the following is not part of a graph:

na) An arrow

nb) A nodenc) An edgend) A vertexn

e) An arc

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29



nWhat is the fastest time that thefollowing list of number could besorted in descending order:

{10,9,8,7,6,5,4,3,2,1}na) No time – it is already sortednb) O(n)

nc) O(nln(n))nd) O(n2)

ne) It depends on the algorithm

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29




nA* search can be used for:na) Finding the shortest route betweentwo stations on the underground

nb) Optimising the parameters of aNeural Networknc) Organising similar objects intomutually exclusive setsnd) Creating compilation CDsne) Decision Planning

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29




nWhich of the following HeuristicSearch Methods is the odd one out?

na) Random Restart Hill Climbing

nb) Stochastic Hill Climbingnc) Genetic Algorithmnd) Hill Climbingn

e) Simulated Annealing

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29



Example Multiple Choice – Part8

nWhich of the following statements is trueregarding bin packing and data clustering?

na) Bin packing is slower than data clustering

nb) Bin packing is used on small sized objectswhilst data clustering is used on large objects

nc) Both algorithms arrange objects into groups

nd) Bin packing is used on 1-dimensional datawhilst data clustering can be used on n-dimensional datane) They perform the same function

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29



Example Essay Type – Part 1

nConsider the following algorithm:

Algorithm 1. MaxArray(A)

Input: An n row by m column Array A

1) Let max = element 1,1 (A(1,1)) of Array A

2) For i = 1 to n

3) For j = 1 to m

4) If A(i,j) > max Then

5) Let max = A(i,j)

6) End If

7) End For

8) End For

Output: max- the largest element in array A

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29




nFor a total of 15 marks:nDescribe the algorithm in words (notpseudo code)

nCompute T(n) for algorithm 1nCompute O(n) for algorithm 1

nHow would you modify the

algorithm to create a new algorithmMinArray?

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29




n The algorithm is designed to locatethe largest value in an array, passedas a parameter. It assumes that the

maximum is equal to the firstelement (1,1) and thensystematically examines each

element in turn, updating themaximum if the current item underscrutiny is larger than the maximum.

This maximum value is then returned

by the algorithm.

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29




nFor T(n) count all variables reads, writesand operators, note we have two inputsizes n and m

Algorithm 1. MaxArray(A)

Input: An n row by m column Array A

1) Let max = element 1,1 (A(1,1)) of Array A 2

2) For i = 1 to n n

3) For j = 1 to m n (m)

4) If A(i,j) > max Then n m (5) [Assume

worse]

5) Let max = A(i,j) n m (4)

6) End If none

7) End For none

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29




nFor T(n) continued...n2

nn

nnm

n5nm

n4nm

nT(n) = 10nm + n + 2

nO(n) = nm

n To create algorithm MinArray

nWe change the > on line 4 to a <nWe would also rename the algorithm

name and results variable

8/4/2019 CS0004 16.1 Exam Revsion %282010-2011%29



Next Topic

n There is none!nHopefully see you next

yearnGood luck!

nAny questions…

cs0004 16.1 exam revsion %282010-2011%29

Documents