Sommaire pour Issue 3 de Coding & Programming The Complete Manual

Coding is everywhere. From your TV through to the International Space Station, you’ll find millions of lines of code controlling and delivering the services that we take for granted. Behind all this code are the programmers who develop our digital world, using a multitude of different languages to weave the fabric of the Internet, operating systems, games and modern entertainment. Whether it’s inside the world’s most powerful supercomputer or automating tasks aboard the ISS, scripting is the key to effective interaction between systems and people. The Complete Coding Manual Series aims to help you get the most from your coding experience. Inside this book, you will find ideas, concepts, tutorials, hints and projects that will take you from being a beginner to an advanced programmer who understands several languages and…

TRUE CONDITIONS Keeping conditions simple, to begin with, makes learning to program a more enjoyable experience. Let’s start then by checking if something is TRUE, then doing something else if it isn’t. STEP 1 Let’s create a new Python program that will ask the user to input a word, then check it to see if it’s a four-letter word or not. Start with File > New File, and begin with the input variable: STEP 2 Now we can create a new variable, then use the len function and pass the word variable through it to get the total number of letters the user has just entered: STEP 3 Now we’ll use an if statement to check if the word_length variable is equal to four, and print a friendly conformation if…

PLAYING WITH PI For this example, we’re going to create a program that will calculate the value of Pi to a set number of decimal places; as described by the user. It combines much of what we’ve learned, and a little more. STEP 1 Start by opening Python and creating a New File in the Editor. First, we need to get hold of an equation that can accurately calculate Pi without rendering the computer’s CPU useless for several minutes. The recommended calculation used in such circumstances is the Chudnovsky Algorithm, you can find more information about it at en.wikipedia.org/wiki/Chudnovsky_algorithm. STEP 2 We can utilise the Chudnovsky Algorithm to create our own Python script based on the calculation. We’ll begin by importing some important modules and functions within the modules: This…

THE IMMUTABLE TUPLE Reasons for having tuples vary depending on what the program is intended to do. Mostly a tuple is reserved for something special, but they’re also used, as an example, in an adventure game where non-playing character names are stored. STEP 1 A tuple is created the same way as a list, but in this instance you use curved brackets instead of square brackets. For example: STEP 2 As with lists, the items within a named tuple can be indexed according to their position in the data range: And so on. However, any attempt at deleting, or adding, to the tuple will result in an error in the Shell. STEP 3 You can create grouped tuples into lists that contain multiple sets of data. For instance, here we…

STRING FORMATTING Since Python 3, string formatting has become a much neater process, using the .format function combined with curly brackets. This makes things easier to follow and, as with most coding, there are other ways to do things but this way is recommended. STEP 1 The basic formatting in Python is to call each variable into the string using the curly brackets: STEP 2 Remember to close the print function with two sets of brackets, as you’ve encased the variable in one, and the print function in another. You can include multiple cases of string formatting in a single print function: STEP 3 We can, of course, also include integers into the mix: STEP 4 There are many different ways to apply string formatting, some are quite simple, as…

WRITE AND CLOSE The write() function is slightly more complex than read(). Along with the filename, you must also include an access mode that determines whether the file in question is in read or write mode. STEP 1 Start by opening IDLE and enter the following (obviously entering your own username location): This code will create a text file, called text.txt in write mode, using the variable ‘t’. If there’s no file of that name in the location, it will create one. If one already exits, it will overwrite it – so be careful. STEP 2 We can now write to the text file using the write() function. This works opposite to read(), writing lines instead of reading them. Try this: Note, the 109, it’s the number of characters you’ve…

LOGGING IN For this example, let’s look to a piece of code that will create user logins then allow them to log into the system, and write the time at which they logged in. We can even include an option to quit the program by pressing ‘q’. STEP 1 Let’s begin by importing the Time module, creating a new dictionary to handle the usernames and passwords, and creating a variable to evaluate the current status of the program: STEP 2 Next we need to define some functions. We can begin with creating the main menu, to where, after selecting the available options, all users will return: STEP 3 The global status statement separates a local variable from one that can be called throughout the code, this way we can use…

RANDOM NUMBERS There are numerous functions within the Random module, which, when applied, can create some interesting and very useful Python programs. STEP 1 As with other modules, you’ll need to import random before you can use any of the functions we’re going to look at in this tutorial. Let’s begin by simply printing a random number from 1 to 5: STEP 2 In our example the number three was returned. However, enter the print function a few more times and it will display different integer values from the set of numbers given, zero to five. The overall effect, although pseudo-random, is adequate for the average programmer to utilise in their code. STEP 3 For a bigger set of numbers, including floating point values, we can extend the range by…

BUILDING MODULES Modules are Python files, containing code, that you save using a .py extension. These are then imported into Python using the now familiar import command. STEP 1 Let’s start by creating a set of basic Mathematics functions. Multiply a number by two or three, and square or raise a number to an exponent (power). Create a New File in the IDLE and enter: STEP 2 Under the above code, enter functions to call the code: Save the program as basic_math.py and execute it to get the results. STEP 3 Now we’re going to take the function definitions out of the program and into a separate file. Highlight the function definitions and choose Edit > Cut. Choose File > New File and use Edit > Paste in the new…

Within this section, you can begin to understand the structure of C++ code and how to compile and execute that code. The fundamentals of C++ will teach you the necessary basics, including using comments, variables, data types, strings, and how to use C++ mathematics. These are the building blocks of a C++ program. With them, you can form your own code, produce an output to the screen and store and retrieve data. Building a good foundation is key to mastering C++, and learning how to structure your C++ code will help you further down the line.…

There’s a satisfying feeling when you program code that asks the user for input, before using that input to produce something that the user can see. Even if it’s simply asking for someone’s name, and displaying a personal welcome message, it’s a big leap forward. User interaction, character literals, defining constants and file input and output are all covered in the following pages. All of which help you to understand more thoroughly how a C++ program works, and enables you to add that personal touch with improved user interaction in your own code.…

#DEFINE The pre-processors are instructions to the compiler to pre-process the information before it goes ahead and compiles the code. #include is a pre-processor as is #define. STEP 1 You can use the #define pre-processor to define any constants you want in our code. Start by creating a new C++ file complete with the usual headers: STEP 2 Now let’s assume your code has three different constants: length, width and height. You can define them with: STEP 3 Note the capitals for defined constants, it’s considered good programming practise to define all constants in capitals. Here, the assigned values are 50, 40 and 60, so let’s call them up: STEP 4 Build and run the code. Just as expected, it displays the values for each of the constants created. It’s…

TRUE OR FALSE? While loops are one of the most popular form of C++ code looping. They repeatedly run the code contained within the loop while the condition is true. Once it proves false, the code continues as normal. STEP 1 Clear what you’ve done so far and create a new C++ file. There’s no need for any extra headers at the moment, so add the standard headers as per usual: STEP 2 Create a simple while loop. Enter the code below, build and run (we’ve added comments to the screen shot): STEP 3 First you need to create a condition, so use a variable called num and give it the value 1. Now create the while loop, stating that as long as num is less than 30, the loop…

IF ONLY If uses a Boolean expression within its statement. If the Boolean expression is true, the code within the statement is executed. If not, then the code after the statement is executed instead. STEP 1 First, create a new C++ file and enter the relevant standard headers, as usual: STEP 2 If is best explained when you use a number-based condition: STEP 3 What’s going on here? To begin, an integer called num was created and assigned with the value of 1. The if statement comes next, and in this case we’ve instructed the code that if the condition, the value, of num is less than 1, then the code within the braces should be executed. STEP 4 The second cout statement displays the current value of num and…

.BAT MAN A Windows batch file is simply a script file that runs a series of commands, one line at a time, much in the same fashion as a Linux script. The series of commands are executed by the command line interpreter and stored in a plain text file with the .BAT extension; this signifies to Windows that it’s an executable file, in this case, a script. Batch files have been around since the earliest versions of Microsoft DOS. Although not exclusively a Microsoft scripting file, batch files are mainly associated with Microsoft’s operating systems. In the early days, when a PC booted into a version of DOS (which produced a simple command prompt when powered up), the batch file was used in the form of a system file called…

USING MORE VARIABLES Here’s a good example of mixing system and environmental variables with some of your own creation, along with a number of external Windows commands. STEP 1 Create a new batch file called list.bat and start it off with the @echo off command. Begin by clearing the command prompt screen and displaying a list of the current directories on the computer: STEP 2 Save and execute the batch file. Within the command prompt you can see the contents of all the files and directories from the root of the C:\ drive; and as any user under Windows has permission to see this, there’s no UAC elevated privileges required. STEP 3 Now, create a batch file that displays the contents of any directory and post it as a text…

THE GOLDEN ERA OF CODE While it may seem a little counterproductive to learn how to code in a language that’s virtually obsolete, there are some surprising benefits to getting your hands dirty with a bit of retro coding. Firstly, learning old code will help you build the structure of code as, regardless of whether it is a language that was developed yesterday, or forty years ago, code still demands strict discipline to work correctly. Secondly, everyday coding elements such as loops, sub routines and so on are a great visual aid to learn in older code, especially BASIC. Lastly, it’s simply good fun. GOING BASIC The easiest retro language to play around with is, without doubt, BASIC. Developed back in the mid-sixties, BASIC (Beginner’s All-Purpose Symbolic Instruction Code) is…

Where to start learning how to code? Remarkably, this is the most difficult step. There are plenty of programming languages out there, and a seemingly unlimited number of tools to help you achieve what you want; but where do you begin? In this section, we look at what you will need to take those first tentative steps into the world of coding. You won’t become a programmer in twenty-four hours, learning how to code correctly takes time and patience, but with a little help, you can master the basics and start your coding journey.…

PLAYING WITH PYTHON As with most languages, computer or human, it’s all about remembering and applying the right words to the right situation. You’re not born knowing these words, so you need to learn them. STEP 1 If you’ve closed Python 3 IDLE, re-open it as you did in the previous page. In the Shell, enter the familiar following: STEP 2 As predicted, the word Hello appears in the Shell as blue text indicating output from a string. It’s fairly straightforward, and doesn’t require too much explanation. Now try: STEP 3 You’ll notice that instead of the number 4, the output is the 2+2 you asked to be printed to the screen. The quotation marks are defining what’s being outputted to the IDLE Shell, to print the total of 2+2…

USER FRIENDLY The type of input you want from the user will depend greatly on the type of program you’re coding. A game, for example, may ask for a character’s name, whereas a database can ask for personal details. STEP 1 If it’s not already, open the Python 3 IDLE Shell, and start a New File in the Editor. Let’s begin with something really simple, enter: STEP 2 Save and execute the code, and, as you no doubt suspected, in the IDLE Shell the program will ask for your first name, storing it as the variable firstname, followed by your surname; also stored in its own variable (surname). STEP 3 Now that we have the user’s name stored in a couple of variables, we can call them up whenever we…

Data is everything. It’s worth more than gold or oil, and with it, you can elect presidents or topple governments, find out the secrets of the universe or predict the money markets. Data is power, so, to get the most from your code, you’ll need to know how to use it and how to manipulate it. This section will introduce you to Python’s ability to cope with data and how it can be organised in your code. We look at how graphics are created and how to read and write data from other sources and output to external files.…

KEY PAIRS A dictionary is like a list, but instead each data item comes as a pair, these are known as Key and Value. The Key part must be unique and can either be a number or string, but the Value can be any data item you like. STEP 1 Let’s say you want to create a phonebook in Python. You would create the dictionary name, and contain the data in curly brackets, separating the key and value by a colon Key:Value. For example: STEP 2 As with most lists, tuples, and so on, strings need to be enclosed in quotes (single or double), while integers can be left open. Remember that the value can be either a string, or an integer, you just need to enclose the relevant one…

TIME LORDS The Time module contains functions that help you retrieve the current system time, read the date from strings, format the time and date, and much more. STEP 1 First you need to import the Time module. It’s one that’s built-in to Python 3, so you shouldn’t need to drop into a command prompt and pip install it. Once it’s imported, we can call the current time and date with a simple command: STEP 2 The time function is split into nine tuples, these are divided up into indexed items, as with any other tuple, and shown in the screen shot below. STEP 3 You can see the structure of how time is presented by entering: The output is displayed as such: ‘time.struct_time(tm_ year=2019, tm_mon=9, tm_mday=7, tm_hour=9, tm_min=6, tm_sec=13,…

WORKING WITH DATES The Calendar module is built into Python 3. However, if, it’s not installed, you can add it using pip install calendar, as a Windows administrator, or sudo pip install calendar for Linux and macOS. STEP 1 Launch Python 3 and enter: import calendar to call up the module and its inherent functions. Once it’s loaded into memory, start by entering: STEP 2 You can see that the days of September 2019 are displayed in a wall calendar fashion. Naturally you can change the 2019, 9 part of the second line, to any year and month you want, a birthday for example (1973, 6). The first line configures TextCalendar to start its weeks on a Sunday; you can opt for Monday if you prefer. STEP 3 There are…

GETTING GUI Tkinter is easy to use, but there’s a lot more you can do with it. Let’s start by seeing how it works, and then getting some code into it. STEP 1 Tkinter is usually built into Python 3, however if it’s available when you enter: import tkinter, then you’ll need to pip install tkinter from the command prompt. We can start to import modules differently than before, to save on typing, by importing all their contents: STEP 2 Although it’s not recommended to import everything from a module using the asterisk, normally it won’t do any harm. Let’s begin by creating a basic GUI window, enter: This creates a small, basic window. At this point, there’s not much else to do but click the X in the corner…

C++ is an amazing programming language. Most of what you see in front of you when you power up your computer, regardless of whether you’re using Windows, macOS or Linux, is created using C++. Being able to code in C++ opens a whole new world for you, in terms of desirable professional skills and the ability to code amazing apps and games. C++ is an efficient and powerful language that’s used to develop operating systems, applications, games and much more in science, engineering, banking, education and the space industry, among others. This section looks at the necessary equipment and software needed to get up and running with C++ for Windows, Mac and Linux systems.…

C++ SETUPS As most, if not all, operating systems have C++ at their core, it stands to reason that you can learn to program in C++ no matter what OS you’re currently using. ⬜ COMPUTER Unless you fancy writing out your C++ code by hand on a sheet of paper (which is something many older coders used to do), then a computer is an absolute must have component. PC users can have any recent Linux distro or Windows OS, Mac users the latest macOS. ⬜ AN IDE As with Python, an IDE is used to enter and execute your C++ code. Many IDEs come with extensions and plugins that help make it work better, or add an extra level of functionality. Often, an IDE will provide enhancements depending on the…

THE IMPORTANCE OF COMMENTING Comments inside code are basically human readable descriptions that detail what the code is doing at that particular point. They don’t sound especially important but code without comments is one of the many frustrating areas of programming, regardless of whether you’re a professional or just starting out. In short, all code should be commented in such a manner as to effectively describe the purpose of a line, section, or individual elements. You should get in to the habit of commenting as much as possible, by imagining that someone who doesn’t know anything about programming can pick up your code and understand what it’s going to do simply by reading your comments. In a professional environment, comments are vital to the success of the code and ultimately,…

STRING THEORY There are different ways in which you can create a string of characters, which historically are all carried over from the original C language, and are still supported by C++. STEP 1 To create a string you use the char function. Open a new C++ file and begin with the usual header: STEP 2 It’s easy to confuse a string with an array. Here’s an array, which can be terminated with a null character: STEP 3 Build and run the code, and ‘Welcome’ appears on the screen. While this is perfectly fine, it’s not a string. A string is a class, which defines objects that can be represented as a stream of characters and doesn’t need to be terminated like an array. The code can therefore be represented…

FSTREAMS There are two main data types within the fstream library that are used to open a file, read from it and write to it; these are ofstream and ifstream. Here’s how they work. STEP 1 The first task is to create a new C++ file and along with the usual headers you need to include the new fstream header: STEP 2 Begin by asking a user for their name and writing that information to a file. You need the usual string to store the name, and getline to accept the input from the user. STEP 3 We’ve included comments in the screenshot of step 2 to help you understand the process. You created a string called name, to store the user’s inputted name. You also created a text file…

LOOPY LOOPS The initialise stage of a for loop is executed only once and this sets the point reference for the loop. The condition is evaluated by the loop to see if it’s true or false and then the increment is executed. The loop then repeats the second and third stage. STEP 1 Create a new C++ file, with the standard headers: STEP 2 Start simple and create a for loop that counts from 1 to 30, displaying the value to the screen with each increment: STEP 3 Working through the process of the for loop, begin by creating an integer called num and assigning it a value of 1. Next, set the condition, in this case num being less than 30. The last stage is where you create the…

IF YES, ELSE NO There are two sections of code that can be executed depending on the outcome in an if… else statement. It’s quite easy to visualise once you get used to its structure. STEP 1 Begin with a new C++ file and the standard headers: STEP 2 Let’s expand the code from the if statement on the previous page: STEP 3 The first line in the code creates the integer called num and gives it a value of 1. The if statement checks to see if the value of num is less than thirty and if it is it outputs “The number is less than 30!” to the console. STEP 4 The else companion to if checks if the number is greater than 30 and if so, then…

A NEW BATCH Throughout this section on batch files we’re going to be working with Notepad, the command prompt and within a folder called ‘Batch Files’. To begin with, let’s see how you get to the Windows command prompt. STEP 1 The Windows command prompt may look a little daunting to the newcomer but it’s simply another interface (or Shell) used to access the filesystem. You can go anywhere you like in the command prompt, as you would with the graphical interface. To begin, click on the Windows Start button and enter CMD into the search box. STEP 2 Click on the search result labelled Command Prompt (Desktop App) and a new window pops up. The Command Prompt window isn’t much to look at to begin with but you can…

SEARCHING FOR FILES Here’s an interesting little batch file that you can easily extend for your own use. It asks the user for a file type to search for and displays the results. STEP 1 We are introducing a couple of new commands into the mix here but we think they’re really useful. Create a new batch file called seek.bat and in it put: STEP 2 The new command in this instance is color (Americanised spelling). Color, as you already assume, changes the colour of the command prompt display. The color attributes are specified by two hex digits, the first corresponds to the background colour of the Command console and the second to the foreground, and can be any of the following values: STEP 3 Now let’s extend the seek.bat…

This section features some fantastic coding projects and ideas that you can use in your own code. Want to add something a little extra to your code? How about creating a loading screen, or some amazing text animations using ASCII characters? There’s code here to track the ISS in real-time, and we even look back at some retro coding, using BBC Micro BASIC, to give you a better understanding of how other forms of code come together and work. There are always more ideas to code, so keep learning and keep coding!…

THE FINAL COUNTDOWN Let’s begin with some example code that will display a large countdown from ten, then clear the screen and display a message. The code itself is quite simple, but lengthy. You will need to start by importing the OS and Time modules, then start creating functions that display the numbers: and so on to 10. It’ll take some time, but it’s worth it in the end. Of course , you can always take a different approach and design the numbers yourself. The next step of the process is to initialise the code settings and start the countdown: And finally, we can add a display for the message: The code in its entirety can be viewed from within our Code Repository: https://pclpublications.com/exclusives, where you’re free to copy it…

ASCII ANIMATION Let’s assume you wanted to create an animated ASCII Happy Birthday Python script, with the words Happy and Birthday alternating in appearance. Here’s how it’s done. STEP 1 First we need to create some ASCII-like text, head over to http://patorjk.com/software/taag. This is an online Text to ASCII generator, created by Patrick Gillespie. Start by entering Happy into the text box, the result will be displayed in the main window. You can change the font with the drop-down menu, to the side of the text box; we’ve opted for Big. STEP 2 Now create a folder in your Python code directory on your computer (call it Test, for now), and open either Notepad for a Windows 10 computer, or, if you’re using Linux, then the currently installed text editor.…

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WHAT WE’RE USING Thankfully, Python is a multi-platform programming language available for Windows, macOS, Linux, Raspberry Pi and more. If you have one of those systems, then you can easily start using Python. ⬜ COMPUTER Obviously you’re going to need a computer in order to learn how to program in Python and to test your code. You can use Windows (from XP onward) on either a 32 or 64-bit processor, an Apple Mac or Linux installed PC. ⬜ AN IDE An IDE (Integrated Developer Environment) is used to enter and execute Python code. It enables you to inspect your program code and the values within the code, as well as offering advanced features. There are many different IDEs available, so find the one that works for you and gives the…

PYTHON PENGUIN Linux is such a versatile operating system that it’s often difficult to nail down just one-way of doing something. Different distributions go about installing software in different ways, so for this particular tutorial we will stick to Linux Mint. STEP 1 First you need to ascertain which version of Python is currently installed in your Linux system. To begin with, drop into a Terminal session from your distro’s menu, or hit the Ctrl+Alt+T keys. STEP 2 Next, enter: python --version into the Terminal screen. You should have the output relating to version 2.x of Python in the display. Most Linux distro come with both Python 2 and 3 by default, as there’s plenty of code out there still available for Python 2. Now enter: python3 --version. STEP 3…

#COMMENTS! A method used by most programmers for keeping their code readable, is by commenting on certain sections. For example, if a variable is used, the programmer comments on what it’s supposed to do. It’s just good practise. STEP 1 We’ll start by creating a new instance of the IDLE Editor (File > New File), and then create a simple variable and print command: Save the file, and execute the code. STEP 2 Running the code will return the line: The value of A is, 10 into the IDLE Shell window – which is what we expected. Now let’s add some of the types of comments you’d normally see within code: STEP 3 Re-save the code and execute it. You’ll see that the output in the IDLE Shell is still…

WORKING WITH LISTS Lists are extremely handy in Python. A list can be strings, integers, and also variables. You can even include functions in lists, and lists within lists. STEP 1 A list is a sequence of data values called items. You create the name of your list followed by an equal sign, then square brackets and the items separated by commas; note that strings use quotes: STEP 2 Once you’ve defined your list, you can call each by referencing its name followed by a number. Lists start the first item entry as 0, followed by 1, 2, 3, and so on. For example: To call up the entire contents of the list. To call the item third from zero in the list (21 in this case). STEP 3 You…

STRING THEORIES We’ve already looked at some list functions, using .insert, .remove, and .pop, but there are also functions that can be applied to strings. STEP 1 The main tool in the string function arsenal is .split(). With it, you’re able to split apart a string of data, based on the argument within the brackets. For example, here’s a string with three items, each separated by a space: STEP 2 Now let’s turn the string into a list, and split the content accordingly: And enter the name of the new list, names, to see the three items. STEP 3 Note that the text.split part contains the brackets, quotes, then a space followed by closing quotes and brackets. The space is the separator, indicating that each list item entry is separated…

INTO THE SYSTEM One of the primary features of the OS module is the ability to list, move, create, delete and otherwise interact with files stored on the system; making it the perfect module for backup code. STEP 1 We can start the OS module with some simple functions to see how it interacts with the operating system environment that Python is running on. If you’re using Linux, or the Raspberry Pi, try this: STEP 2 The returned result, from printing the variable home, is the current user’s home folder on the system. In Step 1 that’s /home/pi, it will be different depending on the user name you login as, and the operating system you use. For example, Windows 10 would output: C:\Users\david\AppData\ Local\Programs\Python\Python37-32. STEP 3 The Windows output is…

PYGAMING As stated, Pygame isn’t an inherent module to Python. Those using the Raspberry Pi will already have it installed. Everyone else will need to use pip install pygame from the command prompt. STEP 1 Naturally, we need to load up the Pygame modules into memory before we’re able to utilise them. Once that’s done, Pygame requires the user to initialise it prior to any of the functions being used: STEP 2 Let’s create a simple, game ready window and give it a title: You will notice that after the first line is entered, you’ll need to click back into the IDLE Shell to continue entering code. In addition, you can change the title of the window to anything you like. STEP 3 Sadly, you can’t close the newly created…

#INCLUDE <C++ STRUCTURE> Learning the basics of programming, you begin to understand the structure of a program. The commands may be different from one language to the next, but you will start to see how the code works. C++ C++ was invented by Danish student Bjarne Stroustrup in 1979, as a part of his Ph.D. thesis. Initially C++ was called C with Classes, which added features to the already popular C programming language, while making it a more user-friendly environment through a new structure. #INCLUDE The structure of a C++ program is quite precise. Every C++ code begins with a directive: #include <>. The directive instructs the pre-processor to include a section of the standard C++ code. For example: #include <iostream> includes the iostream header to support input/output operations. INT…

THE DECLARATION OF VARIABLES You can declare a C++ variable by using statements within the code. There are several distinct types of variables you can declare. Here’s how it works. STEP 1 Open up a new, blank C++ file and enter the usual code headers: STEP 2 Start simple by creating two variables, a and b, with one having a value of 10 and the other 5. You can use the data type int to declare these variables. Within the curly brackets, enter: STEP 3 You can build and run the code but it won’t do much, other than store the values 10 and 5 to the integers a and b. To output the contents of the variables, add: The cout << “\n”; part simply places a new line between…

ESCAPE SEQUENCE When used in something like a cout statement, character literals are also called escape sequence codes. They allow you to insert a quote, an alert, new line and much more. STEP 1 Create a new C++ file and enter the relevant headers: STEP 2 You’ve already experienced the \n character literal placing a new line wherever it’s called. The line: cout << “Hello\n” << “I’m a C++\n” << “Program\n”; outputs three lines of text, each starting after the last \n. STEP 3 If you wanted to insert speech quotes inside a cout statement, you would have to use a backslash as it already uses quotes: STEP 4 There’s even a character literal that can trigger an alarm. In Windows 10, it’s the notification sound that chimes when you…

Loops and repetition are one of the most critical factors of any programming language. Proper use of a loop creates a program that delivers the desired outcome precisely as predicted, without issues or errors. Without loops and decision making events within the code, your program will never be able to offer the user any choice. It’s this understanding of choice that elevates your skills as a programmer and makes for much better code. Creating a successful loop gives the code a beginning, middle and end ready to start again, should the user wish to. It also forms the basis for advanced Artificial Intelligence routines.…

DO LOOPS The good thing about a do… while loop is that it’s guaranteed to run through at least once. It’s structure is: do, followed by statements, while condition is true. This is how it works. STEP 1 Begin with a new, blank C++ file and enter the standard headers: STEP 2 Begin with a simple number count: STEP 3 Now, here’s a look at the structure of a do… while loop. First you create an integer called num, with the value of 1. Now the do… while loops begins. The code inside the body of the loop is executed at least once, then the condition is checked for either true or false. STEP 4 If the condition is true, the loop is executed. This continues until the condition is…

Windows batch files have been around since the early days of Microsoft DOS. They are simple, yet effective, command-line scripts that can be coded to perform a function; covering everything from automation of system processes to creating a command-line based game. Windows 10 may be the most advanced version of Microsoft’s operating system, but it still has the ability to create batch files. Learning how to code and create a batch file will help you discover the deeper elements of the Windows OS; leading you on to more specific administrative concepts such as Microsoft’s PowerShell.…

INPUT, OUTPUT Batch files are capable of taking a normal Windows command and executing it, while also adding extra options and flags in to the equation. STEP 1 Let’s keep things simple to begin with. Create a new batch file called ‘dirview.bat’, short for Directory View. Start with the @echo off command and under that add: Substitute YOURNAME with your Windows username. STEP 2 The new line uses the dir command to list the contents of the directory Batch Files, in your Home directory, dumping the output to a text file called dirview.txt in the root of your Home directory. This is done, so that the Windows UAC doesn’t require elevated permissions, as everything is in your own Home area. Save and run the batch file. STEP 3 You have…

X=MISTAKE, PRINT Y There are many pitfalls for the programmer to be aware of, far too many to be listed here. Being able to recognise a mistake and fix it is when you start to move into more advanced territory, and become a better coder. Everyone makes mistakes, even coders with over thirty years’ experience. Learning from these basic, common mistakes help build a better coding foundation. SMALL CHUNKS It would be wonderful to be able to work like Neo from The Matrix movies. Simply ask, your operator loads it into your memory and you instantly know everything about the subject. Sadly though, we can’t do that. The first major pitfall is someone trying to learn too much, too quickly. So take coding in small pieces and take your time.…