- Trending Categories
- Data Structure
- Networking
- RDBMS
- Operating System
- Java
- MS Excel
- iOS
- HTML
- CSS
- Android
- Python
- C Programming
- C++
- C#
- MongoDB
- MySQL
- Javascript
- PHP
- Physics
- Chemistry
- Biology
- Mathematics
- English
- Economics
- Psychology
- Social Studies
- Fashion Studies
- Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
What are variables and types of variables in C++?
A variable provides us with named storage that our programs can manipulate. Each variable in C++ has a specific type, which determines the size and layout of the variable's memory; the range of values that can be stored within that memory; and the set of operations that can be applied to the variable. A very simple example of a variable is −
int my_val = 5;
Here we have a variable my_val of type int(integer) and having the value 5. More generally variables are defined as −
type variable_name;
Or if you also want to initialize them −
type variable_name = value;
The name of a variable can be composed of letters, digits, and the underscore character. It must begin with either a letter or an underscore. Upper and lowercase letters are distinct because C++ is case-sensitive. Following are the basic types available in C++ −
S.No | Type | Description |
---|---|---|
1 | bool | Stores either value true or false. |
2 | char | Typically a single octet (one byte). This is an integer type. |
3 | int | The most natural size of an integer for the machine. |
4 | float | A single-precision floating point value. |
5 | double | A double-precision floating point value. |
6 | void | Represents the absence of type. |
C++ also allows us to create more complex variables like Enumeration, Pointer, Array, Reference, Data structures, and Classes.
- Enumerations or enums is a data type consisting of a set of named values called elements, members, enumeral, or enumerators of the type. The enumerator names are usually identifiers that behave as constants in the language.
- Pointers are special ints that store addresses of other variables.
- A Reference is a simple reference datatype that is less powerful but safer than the pointer type inherited from C.
- A data structure(struct) is a group of data elements grouped together under one name. These data elements, known as members, can have different types and different lengths.
- Classes are an expanded concept of data structures: like data structures, they can contain data members, but they can also contain functions as members.