CCITcoder
Contents
Introduction to C
DataType and Operation
- Datatypes
- Format specifiers
- Operators
- Keyword/Token
- Cast Operator / type casting
- Formatted I/O
- Unformatted I/O
Conditional statements
Iterative statements
Functions
Array
Pointers
- Introduction Pointers
- call by Value/ Reference
- Passing arrays as argument
- Pointer to Pointer
- Function Pointer
- Dynamic Memory Management
Structures
File I/O
Graphics
Additional Features
Contents
Introduction to C
DataType and Operation
- Datatypes
- Format specifiers
- Operators
- Keyword/Token
- Cast Operator / type casting
- Formatted I/O
- Unformatted I/O
Conditional statements
Iterative statements
Functions
Array
Pointers
- Introduction Pointers
- call by Value/ Reference
- Passing arrays as argument
- Pointer to Pointer
- Function Pointer
- Dynamic Memory Management
Structures
File I/O
Graphics
Additional Features
Data types
Memory Variables
- It is a location in memory where we can store some data.
- A memory variable can be defined by specifying its data type , variable name and optional value.
datatype variablename [ =optional_value ] ;
Data types
- To store different type of data in memory c language provides us different data types.
- According to these data types it is decided how much memory space will be used to store the data and how data will be represented in memory.
- We can group these data type in different category
- Primitive data type (int ,float,double,char)
- Modified data type (long int, unsigned int…)
- Derived data type (arrays)
- User defined data type (struct, union…)
Primitive Data Types
int
- It is used to store whole numbers.
- Size in memory is 2 or 4 bytes depending on compiler and system
- Range 2 bytes ±215 (-32,768 to 32,767 )
- Range 4 bytes ±231 (-2,147,483,648 to 2,147,483,647 )
- For ex: 4117, -458, 0x13a8, 017 etc. datatype variablename [ =optional_value ] ;
char
- It is used to store characters.
- Size in memory is 1 byte.
- It support ASCII character set.
- It can store 256 type of different characters.
- Range is ±27.( -127 to 128 )
- For ex: 'A','z', '$', '7' etc.
float
- It is used to store floating point values with single precision.
- Size in memory is 4 bytes
- float has 7 decimal digits of precision.
- Range (1.2e-38 to 3.4e38 )
- For ex: 3.14f , -0.0124f , 2.015fe+003 etc
double
- It is used to store floating point values with double precision.
- Size in memory is 8 bytes
- double has 15 decimal digits of precision.
- Range (2.2e-308 to 1.8e308 )
- For ex: 3.140163 , -0.01253424 , 2.015657e+003 etc
Modified DataTypes
- Modifiers are C keywords that modify the meaning of Primitive data types.
- It indicates how much memory will be allocated to a variable.
- Modifiers are prefixed with Primitive data types to adjust the memory allocated for a variable.
- C Programming Language has four data type modifiers
- short
- long
- signed
- unsigned
| Datatype | Memory size | Range |
|---|---|---|
| int | 2 bytes(±215) or 4 bytes(±231) |
-32,768 to 32,767 or -2,147,483,648 to 2,147,483,647 |
| short int | 2 bytes(±215) | -32,768 to 32,767 |
| long int | 4 bytes(±231) | -2,147,483,648 to 2,147,483,647 |
| long long int | 8 bytes(±263) | –9,223,372,036 ,854,775,808 to 9,223,372,036 ,854,775,807 |
| unsigned int | 2 bytes(216) or 4 bytes(232) |
0 to 65,535 or 0 to 4,294,967,295 |
| unsigned short int | 2 bytes(216) | 0 to 65,535 |
| unsigned long int | 4 bytes(232) | 0 to 4,294,967,295 |
| unsigned long long int | 8 bytes(264) | 0 to 18,446,744,073, 709,551,615 |
| signed int | 2 bytes(±215) or 4 bytes(±231) |
-32,768 to 32,767 or -2,147,483,648 to 2,147,483,647 |
| signed short int | 2 bytes(±215) | -32,768 to 32,767 |
| signed long int | 4 bytes(±231) | -2,147,483,648 to 2,147,483,647 |
| double | 8 bytes(±231) | 2.2E-308 to 1.8E+308 |
| long double | 10 bytes | 3.4E-4932 to 1.1E+4932 |