C++ Programming for Beginners - the Ultimate Crash Course to Learning Basics of C++ in 24 Hours Or Less! 1530135249, 9781530135240

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C++: C++ Programming For Beginners - The Ultimate Crash Course To Learning Basics Of C++ In 24 Hours Or Less!

Table of contents Introduction Chapter 1 – Getting Through Some Basic Symbols Chapter 2 – Really Important Characters (Really They Are) Chapter 3 – Learning to Think Differently Chapter 4 – Using Classes to Help Build the Structure Chapter 5 – Getting Down with Lists Chapter 6 – Keeping Your Members Safe Conclusion

Introduction Hi there! We’re going to do our best to plow through a little bit of the wonderfully complex and intricate computer language that is known simply as C++. Learning C++ certainly takes quite a bit of time, in fact you could dedicate entire semesters of time to trying to master the little intricacies that are involved with it. Think of it like learning any language. You have to learn the basics of the sounds and how words are pronounced along with their meaning long before you ever get to the stage of actually being able put whole sentences together with fully conjugated verbs and dashing descriptive elements. The same it is with C++. We will be able to go over some of the basics in this crash course so that hopefully you have some sort of sense of the language and that it looks a little less foreign by the time we are completed. Or, at least you will be able to understand why some of the things go where they go, and why that is the case. The basic language is broken down into two main components that are based on a language that is similar to the one that you are reading now, and then the syntax of the computer language that honestly looks just like…well it looks like computer language. It really isn’t legible and doesn’t seem to make much sense whatsoever. It is however the language that the computer speaks and if you want the computer to do what you need it to you are going to have to learn to speak in its language. Just like going to a foreign country, you should at least be respectful and be able to know your way around basic vocabulary. C++ is used to build nearly all of the programs that you have ever used. The purpose of it is to write out a long series of commands that the computer is able to process and turn into a series of executable actions that build upon one another to start performing the functions that you want it to. Most people use one form of editor or another to write the code and then once the code is written it must be converted over into a manner that the computer can use through a compiler. You only need to know that this is the process though because most programs now days (or environments) that provide both of these aspects nicely wrapped up into one simple package like Microsoft’s Visual C++.Net., or you can always get a free version by doing a search online for a public domain shareware version that will easily give you just as much access, especially when you are at the beginning phases of learning your way around coding. Once you have gotten one of the many different environments available for you to start writing code in you are ready to begin. The process isn’t pretty. It doesn’t look flashy, and there certainly aren’t any bells and whistles to getting code written. Unlike many of the website builders that are available nowadays that use visual elements in a more drag-and-drop basis, writing code involves a

boring window that you do nothing but type in. Writing code is certainly not for the faint of heart or those with a short amount of patience, but you have made it this far and clearly have some sort of desire to punish yourself by trying to conquer coding. The good thing about it though is that once you have it down you will be an invaluable resource to many businesses and companies as there is always a need for coders. Plus, you may even be hot on the tail of being able to build your own program that could make you the next overnight sensation. Stranger things have happened. That being said, get ready to roll up your sleeves and prepare to be left with more questions than you have found answers to. That is just the way learning code goes. You will wonder how to do something and you will most likely have to go out there and hunt for ways that other developers have done the same commands in their programs. Thankfully, for the most part the online community of coders are usually more than willing to help out other coders as the process is long and takes many hours of sitting at the computer. Any human contact is welcome. Even if it’s just through a forum. Here we go.



Chapter 1 – Getting Through Some Basic Symbols When you begin to write your first few commands you will notice lots of symbols like “//” and “”and other commands such as “#include”. Most code that people write will begin with a series of comments that are directions that the programmer uses to keep an eye on the fact that the program is heading in the right direction. The lines of code for a program can be near endless and at first glance you might not exactly know what a given code is for. That’s why programmers use the first 6 lines or so to dictate what is going on with the code. These lines begin with “//” and really don’t do anything for the program itself except provide it with a working aim for anyone that may ever encounter a copy of the code. You may also notice if you ever look at a line of coding that most of the lines are relatively short. The traditional standard is to keep the lines at or around 80 characters. This isn’t a necessity, but you will find that it certainly makes scrolling through long lines of code much easier than if you have to keep visually moving your eyes fully across the screen. Every line of code that you write that actually tells the program what to do is referred to as a statement and will always end with “;”. You will fare well if you think of a lot of the process of writing code as something similar to algebra. There is a lot of defining of “If this then that” or X=2-Y or some sort of variation of a variable. You will also learn that C++ is case sensitive. This greatly increases the possibility for the different coding that you can write, but will make it difficult if you happen to forget that you capitalized a certain command in one place and then forgot to do it in another. You name your variables as you create them and it is a wise programmer that learns how to keep the titles of them short and sweet. When you set up variables you will use the command “int x;” or substitute x with whatever letter or number you want to use as the variable. Following the “;” you go ahead and tell the program what the variable equals by typing something like “x=32;” Clearly you are going to be doing more than simply making equations with numbers and letters but the just of the command lingo is that you have to declare what the variable will be and this is done through the “int” command that stands for integer. You can also do “string y” “y=”whatever you want it to be even these words right here”” When you write out a sentence for it to be you have to store the phrase inside of quotation marks. As you see above instead of using the phrase of “int y” when using a string of words, we use the “string y” to dictate that there is a string of characters that fulfill the purpose of the variable. Some other common variables that you use will be the “double”, the “float” and the “char” these all mean (respectively) that you can use a decimal in an integer, a precision number, and of course a single character from the alphabet. Some of the variable can seem a bit odd, but you will learn to get the hang of them the

more that you are required to use them in the different coding strings that you develop and build.

Chapter 2 – Really Important Characters (Really They Are) In each line of code that you see, well most of them at any rate, you will see the use of the backslash a lot. You use the backslash in combination with another character or letter to perform a set action every time that it appears in your code. For instance, if you want to start a new line you would type ‘/n’ in your code. You use ‘/t’ to dictate that there needs to be a tab. “/0” (that’s a zero) to represent that something is null. And lastly as we already covered if you want to represent that something simply a backslash you would use the double backslash, “//”. When you are building up different variables you can assign them to different functions by adding a character in front of the word. The front letter will also help you identify what mixed-mode of expression you are using. For the most part though you will find that it is best not to perform this type of coding but in case you do you would use things like nVariable for ‘int’ and dVariable for ‘double’ and then cVariable for ‘character’ and szVariable for string. That aspect is okay for all intents and purposes but when you begin to mix them so that it says dVariable=cVariable you start to complicate things in a way that is simply not necessary when the programming of the compiler is well capable enough to handle these conversions for you automatically. You will experience this as you code and then it will make sense. For now, though, just know that you can simplify the naming of variables by placing a character or two in front of them. The next set of characters that you will want to learn involve operators that help the program distinguish the difference essentially if something is true or false. Think of it again in terms of ‘if this then that’. If two values are always true no matter what (they have the same value) then you would use a double equals sign “==” in between both variables or values. If there is inequality you use “!=” You are probably familiar with the greater than or lesser than signs. “” they are just as applicable in programming as they are in mathematics. You use “&&” to dictate the word “and” it means that both statements are true on both sides so long as the arguments are true that you use. If only one of them is true than you use these “||” if the statement is true when it is false (I know it doesn’t make sense now) then you use the “!” symbol in between both arguments. You will also need to eventually build loops in your coding. This is a series that will continue while a certain action or condition is occurring. One of the easiest ways to do this is simply to specify it with the word “while” followed by the condition. So you could do something like “WhileStarting” followed by a set of commands marked by the beginning and ending loop sequential characters of “{“ to start and “}” to finish the loop.

These are, of course, just the basics but hopefully they will help you start to recognize some of the characters that you see so that you know a little bit more of what is going on with them. Remember that learning C++ or any code for that matter truly is learning another language. It is going to look foreign and make absolutely no sense at first, until you start to see it more and recognize what is going on will it kick in that it actually makes any sense to you. Just keep at it, and keep expanding your ‘vocabulary’ and remember that much of it depends on what you set each variable and condition to be.

Chapter 3 – Learning to Think Differently Despite the language aspect of coding, which you will inevitably pick up on your own accord over time and with practice, you are going to need to rewire the way you think about things. Right now you are probably like the rest of the world and think in terms of the object that is in front of you. Right now it is whatever device you are using to read this on. It most likely is a smartphone or at the very least a tablet. I highly doubt many of you are actually reading this on a laptop screen let alone a big monitor, but still you could be. For the sake of example let’s say that you are reading this on your smartphone. As you move through the lines looking for some form of useful information you are scrolling along with your thumb. You are really only looking at the words. Your process of retrieving the useful information involves skimming through quickly and not really thinking too much about all the other process that is going on. To start to think like a programmer does, you need to step inside of the machine a little bit more. You need to think about all the circuity that is going on when you do use your brain to signal your thumb to move across the screen of your smartphone. Sure you are swiping the screen along but what sort of coding flow is necessary to make that happen. That is just one part of the code. It is called an instance. Then if you step even further inside of the machine there is the data tower that is sending the information to you so that you can view it. There is a path back from the data tower that came from Amazon, or wherever you happen to have come across a copy of this. Further back from that there was a publisher, there was me the writer, there was the day that I went through, there was the coffee that I consumed in order to make this happen. This backtracking and looking through the many different abstractions that create an event are the ways that you must begin to think when you are doing coding. You have to think about everything that must go into the desired outcome, without thinking solely on what you want the desired outcome to be. If you get to hyper focused on the plain reality of what you see with the objective outlook (i.e. the text in front of you) then you aren’t going to be able to dive down deeper into the matrix of it all to access what is going on behind the scenes. When you are learning coding this process will get easier, then harder, then easier, then even further more complicated than you can ever imagine. It is a wild chase down a rabbit hole that at times will seem like it never ends. Hence why you use those first few lines of the code to remind you and everyone else that might pick up your code what it was you were trying to do. Inevitably there will come a

time when you are simply fed up and no longer wish to continue, as you may be feeling about this book right now. But trust that learning coding in a nutshell basically means that you are going to be learning that you need to let go of everything you ever thought in terms of the superficial aspects of what you see when you use a program. This is why programmers pool together. They are stuck in a real life RPG where hopefully all of the kinks in their code can get worked out. There are always kinks in a code. You will never, no offense, just sit down an pump out the perfect code. It just doesn’t work that way. Our brains aren’t wired for that. But you can practice, and practice, and eventually you will minimize the errors and increase the efficiency of your coding as you learn to do more with less coding.

Chapter 4 – Using Classes to Help Build the Structure When you are writing code there is a stage where you will want to quit using all of the functional codes that we mentioned earlier (and some of the other ones that you are surely to pick up in the beginning) and you will want to start to define classes. Classes are a great way to make sure that all the information you input stays within a set group. When you set a class you define what the class will be. You could write, “class BandStartYear” and then as you build the code around it you would write things such as “displayData(BandStartYear) and the code knows that you are talking about the programming that you designed to input the name of a band and it will spit out the corresponding date that the band started up given the long pages of coding that you have put in with a set amount of bands. You can see imagine that just simply coding for 30 different bands’ and their corresponding start up dates would require lengthy coding to produce a very minimal result. The important thing that you realize is that building classes will help you group everything together so that the program knows which set of commands to apply to your class. Let’s imagine you have made a class that involves something like “class Radio” in order to get the class to start doing things you will use different phrases that are defined as functions that are key to the specific class that you assign them too. When you assign these functions they are known as member functions and they will always refer back to the specific class that you set them in. You could do something like “channel ()” inside of the radio class as a function to define a specific radio station that you know comes in clearly. The program could store lists of applicable radio stations in your area that all come up under “class Radio”. Whenever you go through the process of having to add a member function to a class as with ‘channel’ example, you simply have to use the phrase “addChannel (int, double)” This lets the program know that it will be a number and that it will be a value that will contain a decimal, as your standard radio station does. In order to fully connect this member function to your class you will need to make sure it is connected by typing the following “Radio::addChannel (int,double)” This is essentially the full manner of stating that the function goes along with that specific class. It can be shortened to simply “::addChannel(int.double)” but this would mean that the Channel has nothing whatsoever to do with the Radio class. As you add different member functions you will find that it is always best to keep them all directly in line with the class that they go along with. This will help ease up the stress on your processor but there are certain times when you will find the need to actually put the member function outside of the class. This can be when the member function is an exceptionally lengthy piece of code. To do

this you would then create a source file that is external that your main class would begin to reference when the scenario of the function becomes needed.

Chapter 5 – Getting Down with Lists Lists are commonly used to keep you from having to make a set declaration as to the size of how long an object list will be. A list can go on indefinitely or it can be shortened as much as you want. The problem with lists though is that they aren’t quite as accessible as other forms (such as arrays) considering that you have to go through each process of a list before you reach the portion that you want. Imagine it like the times that you feel out those wonderful forms for different applications online. Many times you would like to skip some of the most unnecessary information and get right to the point of just clicking on the ‘accept’ button, only you can’t. You have to take your time and actually go through every little step in order to get to the point where you can fully move forward. That’s the way lists work. They can work greatly to your advantage, and a linked list can certainly give you great efficiency given its expandability, but remember that it comes at the cost of having to have your user go through every little step. Before you decide to make a list in one of your classes you have to make sure that you have defined the class so that it can actually have a list in it. This is done through the following command: “class LinkableClass”. This leads up to the next important piece of code: “pNext”. This sis the bit of code that will continue the list on to the next portion of the ladder. It gets you through the list by essentially forming a chain for the list. You then continue the list using “//” for each of the different members that are included in the class. When you are starting off the list you use the code: “pNext”, to define that it is the head of the chain. Then at the end when you are finished you simply close with “pHead”. Not necessarily the first thing that you would think of when it comes to closing a list, but then again we are talking about coding terminology here. You have to suspend anything that makes too much sense. Computers talk funny. “pHead” essentially commands the chain to close back to the beginning of it.

Chapter 6 – Keeping Your Members Safe When you are creating member functions for certain classes you have to make sure that they cannot be affected by other commands that reside outside of the given class. This is a process of protecting them more often than not from yourself so that you don’t do any harm to the integrity of the member function the further you delve into your coding. It’s not like you are protecting them with some wildly fail safe code. You are simply making sure they stay where you put them. This process also will help you ensure that the class that you have created continues to function in the manner that you made it. If suddenly another line of your code were start interfering with the member function that you have set up, then the class that you created will no longer function the way that it previously did. This can actually mess up far more than simply the member function that you neglected to protect. This will also enable you to deal with ‘chunks’ of a class in a much easier more organized manner. If you ever need to replace part of it or make changes, you can do so without necessarily jeopardizing the remainder of the class and the other member functions that fall under it. It is also an important part of coding that stays completely out of site from the person that is using the program. This is when you truly get to start to make the magic happen behind the scenes. It’s essentially the electricity that is flowing through your smartphone as you read this. The distinguishing terms for whether your class is public or protected is pretty straightforward in this instance. You use the word “public” in addition to the class to dictate that any of the other member functions that you may add down through the code can also apply to the class. If you want to protect it, you simply add “protected” in front of class to make sure that non-members of the class can’t jump in and start making changes that you don’t want or didn’t anticipate. When you are starting to develop classes, as a general rule of thumb, all programmers take the time to type out one of the two commands as to whether or not the class is public or protected. It is a quick change down the road to go from one or the other, but to keep things in good form, it is ideal to go ahead and make the declaration when you are building a class for the first time in every code.

Conclusion Clearly this is just a quick and simplified crash course when it comes to learning the language of C++. Individuals spend upwards of a year and then some just trying to master enough coding to be able to make a decent and simple game. The process isn’t that difficult if you are just looking to build a simple program or library. But still you would be looking at a few months’ worth of intensive study to get to the point where you are comfortable with it. About all you can do is what you have already done up to this point. Immerse yourself in as much coding speak and jargon as you possibly can and expose yourself to new things with coding on a continual basis. I know we have covered this already, but it really is like learning a foreign language. You could travel to France to learn the language, and it would be completely a mind press without knowing a single bit of the language before you went there. Eventually you would catch on, but it would most likely be through the help of other locals that already speak the language. The same is true with coding. One could argue that you never really truly master it as a language. Think of how many people speak English that are really far from being able to claim anything like complete mastery over the language. Sure they can speak it and get by just fine on a daily basis, but they are not experts. That is sort of how coding goes. You will learn to do some basic things first and then you will add to it. Eventually you will want to do more, and as you do you will encounter a whole new vast set of complexities that will stand in your way like the largest roadblock ever. That’s why there are so many forums for coders. Each coder comes across different roadblocks along the way of building code and sometimes the solution is nothing more than the quick fix of a couple of commands to get the code running but the old saying, doesn’t go something like, “You don’t know if you don’t know.” That’s the way it will be in the beginning. It’s not so much that it is a matter of trial and error, it is more a matter of setting your scope on a destination that you want to achieve with your programming and then diligently setting off on that trail to get to where you are aiming. The more you work with the program you will learn that things change, the whole landscape of coding is evolving as programs are upgraded and changing as well as the operating systems that are performing all of the different fundamental controls that you have included in your code. The response to that is that you will forever by shifting your understanding of the coding language as it is anything but a firm exacting science. It is best to think of the language as more of a tool that is there to help you solve the problem of building the program that you need. Remember that this isn’t the only

language that is out there when it comes to programming. You may find that there is another language that suits you far better and makes more intuitive sense to you. There is also a vast array of new programming interfaces out there now that essentially eliminate the need to get as involved and basic as C++. Now you can build entire programs without ever having to touch a bit of code. You can do it all visually, which for many people is a lot more intuitive when it comes to making a program that is a game or that is going to function in a more visually intensive manner. These types of programs are usually done with more of a building blocks sort of drag and drop setup that one can learn in a single evening spent playing around with the programming ‘language’. Of course like any of the languages that are available out there, knowing how to use it and actually building something worthwhile with it are two completely separate things. If you decide to stick with C++ (and there really is no reason why you shouldn’t) prepare yourself for years of study and continual growth as you push the boundaries of what you understand about the code. There is no short quick answer when it comes to using this specific programming language. It is probably harder to learn and understand than any spoken language that there is. The amount of variables and flexibility that can exist each time that you work toward identifying new problems and conquering them is nearly limitless. The most important thing you can do with your coding is to learn how to recognize a problem when you see it as you are building and to be able to work your way around it before you have set your scope on hundreds of hours of coding and have missed making some of the necessary declarations early on in the coding. This you will come to learn over time as you start small and work your way up to making some of the more intensive programming commands. Remember it’s slow and steady that wins the race and the saying couldn’t be anymore applicable then it is when it comes to coding. If you stick with it though, the reward of being able to write code on this level will boost you to ninja programmer status instantly. C++ is anything but easy. Best of wishes.