I thought that this might be a good idea. Every day, I'll try to post a tip about C++. A lot of you are more qualified to give out tips than me, so if you have a tip, just PM it to me and I'll be sure to give you credit. Thanks guys.
I want to keep all the posts coming from one person, so that's why I want to do the PM system. Enjoy.
C++ Programming Tip 1: Use vectors instead of arrays.
The C++ STL library defines a vector class which gives you a pre-made generic vector. You can use it in the same way as you would a regular array, only a vector is safer to use and more sophisticated.
Select what you want to copy and in doing so you will keep the formatting when pasting it.
You have now created a vector to hold integers. One of the best things about vectors is that memory for them is dynamically allocated. This is perfect for occasions when you do not know the exact number of elements you may need at compile time. Here's an example:
Select what you want to copy and in doing so you will keep the formatting when pasting it.
Note that I never explicitly tell the compiler how large my vector is. At this point in time, it contains 2 elements, but I can easily add another element to the back of the vector. If I need to get the number of elements in the vector, I can simply use the size() member of the vector object.
There are several ways to retrieve values from the vector, including the standard iterator approach supported for all STL classes. The most common way to accomplish this task is subscripting, which is identical to subscripting arrays:
Select what you want to copy and in doing so you will keep the formatting when pasting it.
As you can see getting values from the vector is simple. Clearing the vector is a simple one step process of calling the .clear() member.
Furthermore, vectors allow you to easily insert elements in the middle of them using simple iterator manipulations and the insert() member.
At the end of the day, vectors provide the programmer a sophisticated container. Prefer using vectors to arrays when you have the option.
Although vectors are great, I should mention that they are slower and larger than regular arrays. Most of the time, it is well worth the trade off, but always use discretion when using them. Sometimes arrays are suffice and the situation does not benefit from using vectors. In these cases, you should use arrays, but there are a lot more situations where vectors can make a programmers job easier and safer.
This is only a small overview of how vectors work and by no means comprehensive. If you plan on using them, make sure you look up a few more details about them. They really aren't hard to learn, and it will really help your C++ programming experience.
I think thats more worthy of an article though you may leave it here for the time being until i add comments to the articles section
Very nice though i prefer vectors over arrays since i find vectors much more dynamic and a hell of a lot easier to work with when you are not 100% sure on the size.
I don't know C++ very well, so hopefully reading your articles will help me infer from C# to C++ a little better.
The differences are quite noticable, but hopefully I can soon start coding some easy programs with C++.
Question: So, the main difference between vectors and arrays is that memory for vectors is dynamically allocated, and arrays is not? Also, in C++, can arrays have an unset size as well? (C# can, so I'm assuming yes.)
No. Arrays are static by nature and thus have a set size. When you get comments in the article section, I'll port them over there. Until then, I'll post them here for discussion. The next one will come a little later today.
C++ Programming Tip 2: Do not use C-style strings in C++.
In C, if you ever wanted to use strings, you would need to use a null-terminated array of characters. It was ugly, unsophisticated, and very susceptible to buffer overflows. C++ and it's STL gives you a much better solution; the string class.
Select what you want to copy and in doing so you will keep the formatting when pasting it.
As you can see, changing the string value is simple as well. If you need to access individual characters of the string, you can treat the string as a character array in C. That is, you can easily do something like this:
Select what you want to copy and in doing so you will keep the formatting when pasting it.
Note that if you want to read in more than one word, you will need to use the getline function as opposed to simply using cin like that.
If you want to use C++ strings, but you need to use a C library or something and need C-style string, you can still use the string class. It offers a method called c_str(), which returns the C version of the string defined in that string object. Handy.
Using the find method, you can easily search for substrings inside of the string. This makes a lot of lexical jobs much easier.
One can use the + operator to append a string and the == operator to compare to strings. A lot of the other operators are supported.
These are just a few features of the C++ string. Clearly it is much better than character arrays and you should avoid character arrays in almost all cases when you have the option of using C++ strings. They are a lot safer to use and to be frank, C-style strings are insane.
C++ programming tip 3: Make your destructors virtual.
This tip is from closure.
When you make a virtual method in a class, you flag it to be overloaded down the inheritance chain. This is also true for the destructor of a class.
If you allocate memory in a subclass, it can become easy to forget to free that memory. Making the base class' destructor virtual forces you to explicitly create a destructor for your subclasses, thus helping you keep track of all the memory you should be deallocating.
@Gleb: I'll be alternating between closure's tips and mine daily. The next one is probably going to regard the use of const and references/pointers, so that should satisfy your request. Just wait until tomorrow.
I don't think that any of the points thus far have been very complicated. The last one may have been a little hard to understand if you don't know about virtual functions and destructors. It's okay. It's a great way to learn and pick up thing.
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though you may leave it here for the time being until i add comments to the articles section 
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