C++ Data Types

C++ Data Types

Basic data types such as int, float, char, etc. in C++ programming with the help of examples.

In C++, data types are declarations for variables. This determines the type and size of data associated with variables. For example

int age = 13;

Here, age is a variable of type int. Meaning, the variable can only store integers of either 2 or 4 bytes.

C++ Fundamental Data Types:

The table below shows the fundamental data types, their meaning, and their sizes (in bytes):

Data Type	Meaning	Size (in Bytes)
int	Integer	2 or 4
float	Floating-point	4
double	Double Floating-point	8
char	Character	1
wchar_t	Wide Character	2
bool	Boolean	1
void	Empty	0

Now, let us discuss these fundamental data types in more detail.

1. C++ int:

The int keyword is used to indicate integers.

Its size is usually 4 bytes. Meaning, it can store values from -2147483648 to 2147483647.

For example :

int salary = 85000;

2. C++ float and double:

float and double are used to store floating-point numbers (decimals and exponentials).

The size of float is 4 bytes and the size of double is 8 bytes. Hence, double has two times the precision of float. To learn more, visit C++ float and double.

For example: 

float area = 64.74;

double volume = 134.64534;

As mentioned above, these two data types are also used for exponentials. For example,

double distance = 45E12 // 45E12 is equal to 45*10^12

3. C++ char:

Keyword char is used for characters.

Its size is 1 byte.

Characters in C++ are enclosed inside single quotes ' '.

For example,

char test = 'h';

4. C++ wchar_t:

Wide character wchar_t is similar to the char data type, except its size is 2 bytes instead of 1.

It is used to represent characters that require more memory to represent them than a single char.

For example,

wchar_t test = L'ם' // storing Hebrew character;




5. C++ bool:

The bool data type has one of two possible values: true or false.

Booleans are used in conditional statements and loops (which we will learn in later chapters).

For example,

bool cond = false;

6. C++ void:

The void keyword indicates an absence of data. It means "nothing" or "no value".

We will use void when we learn about functions and pointers.

C++ Type Modifiers

We can further modify some of the fundamental data types by using type modifiers. There are 4 type modifiers in C++. They are:

signed

unsigned

short

long

We can modify the following data types with the above modifiers:

int

double

char

c

C++ Modify Data Type List

Data Type	Size (in Bytes)	Meaning
signed int	4	used for integers (equivalent to int)
unsigned int	4	can only store positive integers
short	2	used for small integers (range -32768 to 32767)
unsigned short	2	used for small positive integers (range 0 to 65,535)
long	at least 4	used for large integers (equivalent to long int)
unsigned long	4	used for large positive integers or 0 (equivalent to unsigned long int)
long long	8	used for very large integers (equivalent to long long int).
unsigned long long	8	used for very large positive integers or 0 (equivalent to unsigned long long int)
long double	12	used for large floating-point numbers
signed char	1	used for characters (guaranteed range -127 to 127)
unsigned char	1	used for characters (range 0 to 255)