What do I find programming interview problems to practice on?

[mizhael]

Dear all,

I am applying for a software engineer job position (C++).

I knew I am going to be grilled with two types of problems at this stage:

(1) C++ Talk or Paper test questions.
(2) C++ programming/coding test questions.

The first one is more about concept, and everything is on paper. There will be no real programming involved.

The second one is going to be more horrible. Because I will have to do the real programming, with or without people monitoring me, and it's within 1-2 hours time limit, and my code has to compile and has to work. Otherwise the interviewer will not even want to look at my code. This is something like working out something under pressure. It's hard because programming involves a lot of debugging and if under pressure, I can be easily stuck in the debugging... On top of meeting basic requirements, they will then look at speed and the smartness of coding... etc.

I decided to use Visual C++. The questions involved in this second type will be some computer problem solving involving some algorithm and some data-structure. I guess it will not be a huge implementation of Black-Red Tree, etc., because I guess that's not doable with 1-2 hours? Of course it will not be too easy something like sorting too...

So my question is: how to prepare and practice for the second type of questions? And are there any good practice problems that can be worked out in 1-2 hours?

Thank you!

[ahoodin]

I suggest that you look at the topical outline for C++ tests at websites such as brainbench.com to see what topics are important in C++. Then get some good C++ references, possibly at your local library, and make sure you know those topics.

Here are a few good texts on Algorithms with C++:
Algorithms and Data Structures in C++ Leen Ammeraal which can be found at:
http://www.amazon.com/Algorithms-Dat...rdr_bb_product
Which also covers all of the algorithms you will probably need to know on your test.

Algorithms in C++ by Robert Sedgewick
http://www.amazon.com/Algorithms-Par.../dp/0201350882
http://www.amazon.com/Bundle-Algorit...7390587&sr=1-2

I suggest looking at an O'Reilly book: Mastering algorithms with C. I realize this is not C++ but it has some pretty great information on the all the concepts you mentioned, as well as explanations and diagriams.

On top of that if possible you use the STL, alot of important Algorithms are already implemented for you such as list, queue, stack, and so fourth. So if you are comfortable with STL that will be really great because you can solve problems without having to reduntantly code algorithms with existing generic implementations.

Try to conceptually solve the problem in the abstract, and then write code.

[mizhael]

Thanks a lot! Yeah, I would like to use STL because it is really convenient in terms of using these components. Then lots of data structure books talking about link-lists are not useful because I can directly use STL. However, are there any good test problems that I can practice on? I am not sure what type problems are meaningful test problems with difficulty level such as 1 problem in 1 hour.

An equivalent question of asking for "sample test problems" can be: where can I find good books, good codes, good websites, good code snippet repository that have a lot of good meaningful examples of how people use those algorithms and STL?

[Lindley]

Well, www.cplusplus.com has examples on most of their reference pages....

[mizhael]

In fact, I realize the test problems can also be not to play around with the data-structure and/or STL stuff. They can be more like a brain-teaser, and ask you to work out some program to do something with a stringent space or time requirement.

[mizhael]

Well, www.cplusplus.com has examples on most of their reference pages....

but those are not algorithm or problem solving examples, they are language learning examples...

[ahoodin]

They can be more like a brain-teaser, and ask you to work out some program to do something with a stringent space or time requirement.

This is true. In some cases the problems are good, in others the problems and the questions are almost pointless. It can be very hard to study for these kinds of questions unless you get into a regular habit of it. They are meant to show that you have the ability to solve problems small and large.
I recently enjoyed browsing Programming Pearls:
http://www.amazon.com/Programming-Pe...7415645&sr=8-5
It actually has a section on Algorithms, and covers alot problem solving skills for programming.

Facebook and other Social networks are starting to take swipes at getting into recruiting (monsterboard and careerbuilder watch out!).
http://www.facebook.com/jobs_puzzles/

LinkedIn is already making finding a job a social excercise.
http://www.linkedin.com/

I was recently asked this old problem at an interview for a C++ position, that I remember getting in a CS class one day:

Find a way to make the following C program fragment print 42 dashes, by changing only one character. Then find two more!

int i, n = 42;
for (i = 0; i < n; i--)
  printf("-");

True it is a pretty simple problem, but it is an excercise in efficiency, especially when you in an interview.

Don't forget to read up on the company you are interviewing with, and try to know something about the product.
It will impress your interviewers if you did your Homework, and show that you are taking interest.

[mizhael]

Okay! You just have to change "i < n" into "-i<n".

But these type of questions won't be real-time coding test. Remember the coding test will be 1 hour per problem. And the code has to be working, otherwise the interviewer won't even look at it.

So I am looking for that type of real coding questions to practice on...

[ahoodin]

there are 3 easy 1 character changes that can be made to the original for loop to make it work. What I mean is from the original loop, make a character change that will make it work. Now go back to the original loop code and make another single character change.

Ok Now for those problems you wanted:

http://www.softwareinterview.com/

Exceptional C++ / 47 Engineering Puzzles, Programming Puzzles and solutions online format:

http://books.google.com/books?hl=en&...result#PPP1,M1