Variables in C++ are used to store data. A variable is a named memory location that can store a value of a specific data type. Here are the key aspects of variables in C++ along with examples:
To declare a variable, you specify its data type followed by a name.
You can optionally initialize a variable when declaring it.
You can change the value of a variable using the assignment operator (=).
The scope of a variable determines where it can be accessed in your program. A variable's scope can be either global or local.
Variables declared outside of any function or block have global scope and can be accessed from anywhere in the program.
Variables declared within a function or block have local scope and are only accessible within that function or block.
The lifetime of a variable determines how long it exists in memory. A variable's lifetime can be either static or dynamic.
- Static variables: Static variables are allocated in memory when the program starts and are destroyed when the program ends.
- Dynamic variables: Dynamic variables are allocated in memory when they are needed and are destroyed when they are no longer needed.
Constants are variables whose values cannot be changed after initialization.
Variable names are case-sensitive and must start with a letter or underscore. They can contain letters, digits, and underscores.
Variables are named storage locations used to store and manage data. They are declared with a specific data type, can be initialized with values, have a scope that defines where they can be accessed, and can be either global (accessible throughout the program) or local (restricted to a specific function or block). Understanding how to declare and use variables is essential for data manipulation in C++ programs.