Style and Enumerators [closed] - c++

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So, in the process of taking a data-structures class (in C++), my professor wanted us to manipulate a linked list of playing cards. That doesn't matter however, what I am interested in is why she did not use an enumerator to represent the suites.
In her code, she used strings to hold the suite of a card. This seemed inefficient because she wanted us to sort them based on suite, under the circumstances, it would have been considerably easier if she had used an enumerated type instead of a string. The string did not offer any help either, because in printing the suite, she output a Unicode character, roughly doubling the length of her function, simply because she did not use an enum.
Is there any reason for her to have done this, or does she simply have strange preferences when it comes to code style?

If you really want to know what your professor's reasoning is, you have to ask your professor. I can only speculate.
But if I were to speculate, I would guess that there are two possible reasons why your professor chose to use strings as descriptors for these attributes.
She is trying to keep the code simple and easy for newbie C++ programmers to understand. Whether the means meet the goal is debateable.
(Personal bias alert) Professors and others in academia, with no real-world experience, often do and teach things that I would consider to be highly sub-optimal.

My guess would be that she either had not considered that approach or that she wanted to test your ability to work with sorting strings.
Code examples might help in that they might clarify what she did and what you think she should have done.

The likely answer is that she just didn't think about the problem she was using to demonstrate whatever she is trying to teach you. That is, she wanted you to focus on sorting (for example), and probably took some code written by someone else and just adapted it to that purpose without much thought.

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c++ cout vs printf() [closed]

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After learning about c++ through a couple different sources, I found conflicting advice concerning the use of cout/printf(). One source said that printf(), and I quote:
... does not provide type safety, so it is easy to inadvertently tell it to display an integer as if it were a character and vice versa. printf() also does not support classes, and so it is not possible to teach it how to print your class data; you must feed each class member to printf() one by one.
So, the more important thing to me would be the readability factor of using printf(). On the other hand, another source mentioned that cout, with its use of the overloaded operator <<, uses more instructions to execute and can therefore be more expensive in terms of memory over a large program. Although, the person who said this was a systems programmer, in which every bit of performance is vital. But say I wanted to go into game or application development.
Would the performance differences between printf() and cout matter all that much?
In general, does it really matter what I choose to use in an application program?
Thank you for any input.
You would measure the differences on your particular implementation for your specific use case and determine that for yourself.
I would say both lines of reasoning in the question have merit, but you can't generalise about performance.
If you want to go into game or application programming, printf/cout won't be needed too much. The only use in these cases is for debugging.
If you really need to use printf/cout a lot, the difference will be when writing a huge amount of data, otherwise you don't need to bother.

AI for time table generator software [closed]

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I am trying to develop a time table generator software for my college. Obviously it requires a great deal of constraint satisfaction i.e. I need to satisfy a lot of rules in order to generate a bunch of time tables where classes do not clash. After doing some research and reading this article, I feel I need to use some AI in it. Now, I am a complete newbie to AI. Can anyone tell me which algorithm will work best in my case?
The simplest algorithm that you can use for this problem is genetic algorithm (or any other evolutionary algorithm). Solving this problem using GA is very simple but yet effective. There are lots of papers and codes that have used this approach for this problem.
If you have few rules and constraints, you may want to use exact straightforward techniques like backtracking with CSP heuristics to speed it up, but if there are lots of classes and constraints, I suggest Genetic Algorithm.
Well, not a trivial task indeed. Problems like this one are VERY hard to solve.
Here I can recommend you two things:
Use an existing CSP/COP solver and describe your constraints in its language. These solvers are very good, fast and tuned, being developed for years.
Educate yourself in the area of Discrete Optimization (there was a course at coursera.org with the same name which was great). Only after you grasp the basics of how these things work can you try to write your own solver. But let you be warned! Discrete optimization is pain and suffering :-).
This is by no means a suitable place to just tell you how CSP/COP works. It is a very broad and difficult field.
I wish you good luck!

How to approach a C++ parser [closed]

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I am wanting to have a go at a C++ parser for a formatter I am making.
You can obviously open a file and use getline(..) or get(), is this reasonable way of starting things off and then working out a system using vector arrays and hence creating loads of arrays and somehow structuring out and processing what you are doing from there. For example say I wanted to find ever function in a source file, all functions have the common syntax, "(){" once whitespace has been removed, so do you just look for common delimeters to parse out the sections into arrays. I suppose I will learn as I go.
Or I also assume there are tried and tested ways of doing this, and I would likley just be reinventing the wheel as they say.
C++ is a language that is quite hard to parse in the first place. So if you want anything other that really trivial C++ code to be "understood" by your parser, you are definitely better off starting with an existing product.
The Clang frontend library would perhaps be a good starting point.
There are also a number of "source to source" conversion examples based on clang. Here's one of them: http://eli.thegreenplace.net/2012/06/08/basic-source-to-source-transformation-with-clang/

What can a second year computer undergrad do which might be considered worthwhile in the future? [closed]

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Besides taking classes I mean. I want to make myself stand out from the crowd. I am very good at building logic/algorithms. Like I can implement any problem in C. But I don't know how to harness it! Like what to code!?!
All I have made upto this point is games that too in C's console, using ASCII and character arrays. Snake, Sudoku (making a puzzle and solving too), rip-off of Mario Bros., tictactoe with AI. But making games won't get me anywhere.
I was wondering if I could get suggestions from you guys?
I know C++/C and a little Java. I have just got started with data structures. So, it would be great if it would be relevant to data structures. I know about most trees and types of data structures. Thanks a lot for your help.
I know it's off topic but I have nowhere else to turn to.
Pay attention in your finite automata classes. Learning the basis of all languages makes "knowing" a language irrelevant.
If your school offers it, take some business computer systems classes.
Try to get some project management experience under your belt. This could be done by doing work for charity or an internship for a prof.
Of course there is always open source projects as well.
Get a job. I was working for a small development shop as a second year student.
Open your own company, and start doing some mobile apps. The sky is the limit.
If you want to have long term impact, you can do one of two things:
Be a genius, and invent a new gizmo everybody needs. [Extra points].
Build a foundation for something. Add to it cleanly, continuously. Eventually it will have enough mass to have an impact.

Ideas for storing and operating on huge numbers in C++ [closed]

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I am supposed to build a program for storing and handling huge integers. I know that there are many answers out there but I need ideas that I can implement easily, bearing in mind that I can use any of the basic concepts of C/C++.
How should I go about it?
This is the first time I am asking a question here so please correct me if I am wrong about anything.
Edit: Actually what I wanted to know was how should I go about storing a huge integer... Obviously an array is what comes to mind at first glance but are there any other methods out there at the basic level?
EDIT2: I came across a very nice solution to this problem a while ago, but was just a bit lazy to put it on here. We can use the concept of number systems to deal with huge numbers. We can declare an array that holds the co-efficient of powers of 256, thus obtaining a base 256 system. We can then use fundamental concepts like those of the various number systems to obtain our required results.
Matt McCutchen has a Big Integer Library
If you want to do this yourself his code would be a great starting point. As you can overload arithmetic operators in C++ it is not too difficult to make a new BigInteger class and make this handle any number of bits per integer.
There is also a stack overflow answer to this question: here
I consider this as a question about theory, as such I suggest to browse the internet using the right keywords for documents/articles or to take a sneak peek at libraries that are implementing this feature and are well tested, this projects also tend to offer a mailing list or a forum where developers can communicate, it can be a good place to start writing about this stuff.