Programming is essentially the manipulation of many variables. The basic variable data types which C++ variables can assume are: int (integers), char (characters) and doubles (real decimals). Declaring a variable simply means letting the computer know that you want to reserve a spot in memory for it. Here is an example of declaring a variable:
Defining (or initializing) a variable is giving it a value. Variables can be defined at their declaration:
Of course, variables can be assigned values at a later time, too:
It is important to note that characters are represented by numbers in the computer, and a char variable can be assigned a numerical value.
Characters, Escape Sequences, and Strings
Some characters do not have their own symbol and must be referenced by an escape sequence. Some escape sequences are: '\\' -- backslash '\'' -- single quotation mark '\"' -- double quotation mark '\b' -- backspace '\n' -- new line '\r' -- carriage return '\t' -- tab
A string is a sequence of characters ending in the null character (whose escape sequence is '\0'). As a beginner, you can usually ignore this definition because strings are usually simply written as constants between double quotes, such as: "florsheim" or "Enter the quantity of shipments:\t"