Data Type and Classification of Data Type with Examples

Data Types in C

Data types define the type of data a variable can store in a C program. They help allocate the appropriate memory size for variables and ensure proper data handling.

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Classification of Data Types

C provides several data types, broadly classified into the following categories:

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1. Primary Data Types (Basic Data Types)

These are the fundamental data types used to declare variables.

Data Type	Description	Example
int	Stores integers (whole numbers).	int a = 10;
float	Stores floating-point (decimal) numbers.	float b = 3.14;
double	Stores double-precision floating-point numbers (more precision than float).	double c = 3.14159;
char	Stores single characters.	char d = 'A';
void	Represents no value (used for functions that return nothing).	void myFunction();

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2. Derived Data Types

These are data types derived from primary types to handle more complex data.

Type	Description	Example
Array	Collection of variables of the same type.	int arr[5] = {1,2,3,4,5};
Pointer	Stores memory addresses of variables.	int *ptr; ptr = &a;
Structure	Combines variables of different types.	struct Point { int x; int y; };
Union	Combines variables of different types but shares memory.	union Data { int i; float f; };
Function	Block of code that performs a specific task.	int add(int a, int b);

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3. Enumeration Data Type

Used to define a set of named integer constants.

Type	Description	Example
enum	Represents a user-defined type with constants.	enum Color {Red, Green, Blue};

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4. User-Defined Data Types

Users can create their own data types.

Type	Description	Example
typedef	Used to create an alias for an existing type.	typedef unsigned int uint;
struct	Combines multiple types into a single unit.	struct Point { int x, y; };

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5. Data Modifiers

C provides data type modifiers to alter the size and range of data types.

Modifier	Description	Example
short	Reduces the size of an int.	short int a;
long	Increases the size of an int or double.	long int b;
unsigned	Only positive values allowed (extends range).	unsigned int c;
signed	Both positive and negative values.	signed char d;

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Examples of Data Types

 

#include <stdio.h>

int main() {
// Primary Data Types
int age = 25;
float height = 5.9;
char grade = ‘A’;

// Derived Data Types
int scores[3] = {95, 85, 90}; // Array
struct Point { int x, y; }; // Structure
struct Point p = {10, 20};

// Enumeration Data Type
enum Color {Red, Green, Blue};
enum Color myColor = Green;

// Data Modifiers
unsigned int distance = 150;

// Print the variables
printf(“Age: %d\n”, age);
printf(“Height: %.2f\n”, height);
printf(“Grade: %c\n”, grade);
printf(“Scores: %d, %d, %d\n”, scores[0], scores[1], scores[2]);
printf(“Point: (%d, %d)\n”, p.x, p.y);
printf(“Color: %d\n”, myColor); // Outputs 1 for Green
printf(“Distance: %u\n”, distance);

return 0;
}

 

Summary of Data Types

Category	Examples	Usage
Primary	int, float, char	Store basic data like numbers and text.
Derived	Arrays, Pointers, Structs	Handle complex data structures.
Enumeration	enum	Manage named constants.
User-Defined	typedef, struct	Create custom data types.
Modifiers	short, long, unsigned	Adjust size/range of primary types.

By understanding these classifications, you can use the appropriate data types to optimize your C programs!