By Natasha Lomas, 22 October 2008 14:41
NEWS
As well as getting top GCSE and A-Level grades, would-be computer science students applying to Oxford University have to sit a written maths test and undergo at least two interviews as part of what the university terms a "rigorous" selection procedure for its computer science undergrad courses.
But what kind of questions can prospective students expect to be dealt in the interview - often the most feared part of the Oxbridge assessment process?
Interview questions previously used by the university's computer science department include the following problems:
- Death by Chocolate: You are locked in a room with your worst enemy. On a table in the centre of the room is a bar of chocolate, divided into squares in the usual way. One square of the chocolate is painted with a bright green paint that contains a deadly nerve poison. You and your enemy take it in turns to break off one or more squares from the remaining chocolate (along a straight line) and eat them. Whoever is left with the green square must eat it and die in agony. You may look at the bar of chocolate and then decide whether to go first or second. Describe your strategy.
- Tidy Boxes: You are given 10 boxes, each large enough to contain exactly 10 wooden building blocks, and a total of 100 blocks in 10 different colours. There may not be the same number in each colour, so you may not be able to pack the blocks into the boxes in such a way that each box contains only one colour of block. Show that it is possible to do it so that each box contains, at most, two different colours.
- Monkey Beans: An urn contains 23 white beans and 34 black beans. A monkey takes out two beans; if they are the same, he puts a black bean into the urn, and if they are different, he puts in a white bean from a large heap he has next to him. The monkey repeats this procedure until there is only one bean left. What colour is it?
- Missing Numbers: Imagine you are given a list of slightly less than 1,000,000 numbers, all different, and each between 0 and 999,999 inclusive. How could you find (in a reasonable time) a number between 0 and 999,999 that is not on the list?
At Oxford, computer science falls into the Mathematical, Physical and Life Sciences Division and candidates can choose to apply for a three-year BA or a four-year Masters in computer science, or mathematics and computer science. The university says it accepts and encourages applications "from candidates who have little or no experience of programming computers".
According to the computer science course description on the university website, the Oxford course "concentrates on bridging theory and practice, including a wide variety of hardware and software technologies and their applications. The course is designed to equip students with the fundamental understanding and practical skills needed by the potential leaders of a demanding profession".
Students keen to get their tech stripes at Oxford will need "a sound understanding of mathematical ideasÂ… both for potential applications such as scientific computation, and for reasoning rigorously about the specification and behaviour of programs". The website adds that practical skills are also important and the majority of course subjects are "linked with practical work".
Think you have the best Death by Chocolate strategy? Post a Reader Comment below outlining your solutionÂ…
Comments
There are 15 comments. Join the discussion
1. anonymous
If the number of chocolate squares are even then you want to go first. If the number of chocolate squares is odd then you want your enemy to go first.
2. Dale
If the chocolate bar has an even number of pieces go first otherwise go second.
Since a line has two ends you can always take a piece from either end, therfore ensuring the last piece eaten is the green one.
3. Lever
DBC's the easiest one there... if there's an odd number you let your opponent go first. However the "quiet" problem with that Q is who's gonna "break off" the chocolate and touch the painted-on nerve poison to get the remaining "safe" piece?
The questions all sound rather stupid and totally impractical but I'm sure it's good for lateral thinking and appearing on University Challenge. There are no beans or poison in the daily grind of most of us techies...
4. John McBryde
If there are an odd number of squares let the opponent go first.
Even number I go first.
5. James Collins
From GNVQ IT course I seem to remember that you can pick last if:
*you have an even number of pieces. *you go second
*you make sure that the total number of pieces taken in each round by yourself and opponent total an amount divisable by 4.
If odd then one round needs to be divisable by 4 -1
So if you reverse this you can make him always go last?
Would have to double check this as last went over this about 10 years ago and took me long enough to work it out then.
6. Matt
No matter how many peices... what has any of that got to do with the real world IT work place? No wonder I end up working with IT Graduates who've got no idea about real world computing if that's the quality of questions asked! What a load of bull!
7. Cassandra
I notice no-one tackled the others only the chocolate one. Something is very seriously wrong with this approach to Information Technology, is algebra and maths the only factors in selection for IT ability?
Does this faculty restrict its field to bits of math and hardware? Is human perception, information definition and semantic manipulation not thought to have any relevance? These problems are solvable if you spot the math trick if you have seen it before and can count. Where does any understanding of human interaction with information come in if at all?
8. anonymous
Continue the process of alternately eating the blocks of chocolate, until down to the last two or three. Then grab my throat, fall writhing to the floor and feign dying a ghastly death.
Hopefully this will make the opponent think you were both being fooled and that the coloured block was not the poisoned one after all, and greed will seduce him to eat it instead!
9. Karen Challinor
if you have r rows and c columns of chocolate then your objective is to make your opponent take the last piece in any row or column, you can take as many pieces as you want from either a row or a column but you must always leave a piece in that column for your opponent to take because eventually it will be the poisoned one
so if the minimum of r or c is odd you go first otherwise you go second
10. Radical Meldrew
I agree with Matt, what has a potential James Bond scene got to do with IT? The nearest I have ever got to this was working for a graduate CIO who we called 'Jaws' because of his prominent silver dentistry work and his colossal budget ambtions which could have financed a film or two. After a short spell at the helm, he sunk without trace!
11. Adam Byrne
Re: Monkeys and Urns
The bean that is left is white.
Simple answer is that there are an odd number of whites that, by way of logic, are removed an even number at a time (zero or two). There are an even number of blacks that are removed one at a time.
Even if you are left with one white and all blacks and you are lucky enough to pick a black and a white then you'll remove one white and one black, replacing them with one white.
12. Richard
Why live by Oxbridge rules?
How interesting that even normally rebellious Silicon readers go weak at the knees when faced by Oxbridge types: The types who have brought the UK into its current mess?
So, my answers to the chocolate dilemma is a series of questions, including:
Why have we been locked in the room?
Why do I have to eat the chocolate?
Will the survivor actually be released?
If I form an alliance with my "enemy" can we both survive?
Who is responsible for this fiasco?
13. anonymous
What I found interesting is that so few comments on here reflect an understanding of the question, which is an absolutely essential part of working in IT ! Where does it say (as assumed by most) that you have to take one square at a time ?
14. anonymous
I say go first. Eat everything except the green piece and leave that for you enemy. Enemy now has the choice of eating the green piece or dying of starvation as you have eaten enough calories to sustain you.
15. Michael Spivey
All of these questions are taken from the Oxford University Computing Laboratory website. I am the college tutor who wrote the admissions pages on the site, so I was interested in all the comments here. As people have seen, we are definitely not looking for any specific computing knowledge in our interview questions. And we have to be fair to candidates who have learnt any one of a huge number of programming languages, from Visual Basic via Pascal to Python, as well as ones who have not studied IT formally at all.