Often, especially at the start of semesters, I get a lot of questions about how to write very simple programs. Typically, the problem to be solved is to read in a few numbers, do something with them, and write out an answer.
Classes are declared in the following order: public member functions, protected member functions, private member functions, protected data members, and private data members. No data members may be declared public.
Take warnings to heart: Use your compiler's highest warning level. Require clean (warning-free) builds. Understand all warnings. Eliminate warnings by changing your code, not by reducing the warning level.
The first edition of this book both introduced the C language to the world and set a standard for clear language tutorials with a consistant style of presentation. The second edition accounted for changes in C introduced by the ANSI C standard. However, as with any short work, these books provide little advice about structuring large programs or other software engineering issues, and the C style...
Now that you know what a function is, let's look at function syntax. We've already seen that a function can take some inputs, do some stuff, and then produce an output.
Up until this point, every line of code we've shown you has done a simple task, such as performing an arithmetic operation, or checking a boolean condition, or assigning to a variable. Functions allow you to do a whole lot in one line of code. Instead of performing a simple task, a single line of code can display a menu of choices, or compute complicated three-dimensional transformations, or even...
So, upon initial execution of the loop, the integer variable i is set to 1. The statement total = total + i; is executed and the value of the variable total becomes 1. The step code is now executed and i is incremented by 1, so it's new value is 2. The test_condition is then checked, and since i is less than 11, the loop code is executed and the variable total gets the value 3 (since total was 1,...
The next branching statement is called a switch statement. A switch statement is used in place of many if statements.Let's consider the following case: Joel is writing a program that figures interest on money that is held in a bank. The amount of interest that money earns in this bank depends on which type of account the money is in. There are 6 different types of accounts and they earn interest...
When a programmer is crafting a program, it is good practice to break the program down into pieces that can be thought of independently. Once the program has been completed, we can think of its execution as being a series of these pieces that work together in a certain sequence. These pieces then pass the control of the program between each other. While one piece has the control, the other pieces...
What will be the value of result? The answer depends on the precedence of the operators. In C++, the multiplication operator (*) has higher precedence than the addition operator (+). What that means is, the multiplication 5 * 6 will take place before either of the additions, so your expression will resolve to 4 + 30 + 2 , so result will store the value 36.
In any programming language, and especially in C++, it's important to have at least a cursory understanding of what the computer is doing "behind the scenes". Since we're talking about variables in this chapter, it's important to understand how a computer stores the information in variables.
A variable type is a description of the kind of information a variable will store. Programming languages vary regarding how strict they require you to be when declaring a variable's type. Some languages, like Perl, do not require you to announce the type of a variable. Other languages require you to declare some variables as numbers and others as text-strings, for example. C++, a strongly-typed...
A variable is a place to store a piece of information. Just as you might store a friend's phone number in your own memory, you can store this information in a computer's memory. Variables are your way of accessing your computer's memory.
Before talking about operators, we'll take a quick aside into booleans, since we'll need to know what a boolean is before discussing operators. A boolean value is one that can be either true or false. No other values are allowed. Booleans and boolean operations are at the heart of programming. Many times in a program, you'll want to do one thing if a certain condition is true, and a different...
Depending on your computer and your compiler, the process of compiling your program varies. For now, we'll assume that you are using a UNIX machine and the gcc compiler. Gcc is a free compiler which is available on virtually all UNIX systems.