Skip to main content

Pointer In C Language

          Introduction To Pointer:
About Pointer:-
*POINTER is a variable whose value is the address of another variable
*Every variable is a memory location and every memory location
 has its address defined which can be accessed using ampersand(&)
 operator,which denotes an address in memory
*Dynamic memory allocation,cannot be performed without using pointers.
Let's start learning them in simple and easy steps.
pointer variable declaration:-
data_type *variable_name;
*The asterisk (*) used to declare a pointer is the same asterisk used for
  multiplication.
some of the valid pointer declarations:-
int *in;            //pointer to an integer 
double *db;  // pointer to a double 
float *fl;        // pointer to a float 
char *chr    //pointer to a character 
*The only difference between pointers of different data types
is the data type of the variable or constant that the pointer points to.
Implementation Of Pointers:-
This is devided into 3 steps:-
1)define a pointer variable,
2)assign the address of a variable to a pointer
3)access the value at the address available in the pointer variable by using 
unary operator*Which returns the value of the variable located at the address
Example Program:-
#include <stdio.h>
int main ()
{
int a = 20; // actual variable declaration 
int *i;     // pointer variable declaration 
i = &a;    // store address of var in pointer variable
printf("Address of a variable= %x\n", &a);
/* address stored in pointer variable */
printf("Address stored in i variable: %x\n", ip );
//access the value using the pointer
printf("Value of *i variable= %d\n", *i );
return 0;
}
The Output Of This Program Will Be:-
Address of a variable= d2051594
Address stored in i variable: d2051594
Value of *i variable= 50
A Null Pointer:-
*A pointer that is assigned NULL is called a null pointer.
*The NULL pointer is a constant with a value of zero.
*It Is defined in several standard libraries.
Example Program:-
In This Example We Will Check The Value Of Null Pointer.
#include <stdio.h>
int main ()
{
int *ptr = NULL; //null pointer declration
printf("The value of Null ptr is = %x\n", ptr);
return 0;
}
The OutPut Of Given Program Is:-
The value of Null ptr is = 0
                 
                                         -:Please Share This:-
                                       -:Thank U all:-



















Labels:

Comments

Post a Comment

Popular posts from this blog

Types Of Array In C language

Two Dimensional Array :- * It Is The Combination Of Two One Dimensional Array * It Is Used To Implement Matrix Operation . *A two-dimensional array can be considered as a table which  will have 'a' number of rows and'b'number of columns. Declaration Of Two Dimensional Array:-   data_type Array_name [size of row][size of column]; For Example:- int matrix[3][4]; in above example we will store a matrix of 3*3. This Will Cleared From Following Figure:- *It can be represented a[i][j].where i and j represents  row and column respectively. Initialization Of Two Dimensional Array:- let us consider an array "float a[3][3]"then it will be initialized float a[3][3]={                {1.2,2.3,4.3} //initializers for row indexed by 0                {2.1,2.2,2.3} //initializers for row indexed by 1                {3.1,3.4,3.6} //initializers for row indexed by 2 ...
Post a Comment
Read more

Basic Syntax Of "C" Language

1).Tokens In C Language:- A C program consists of various tokens and a token is either a keyword, an identifier, a constant, a string literal, or a symbol. For example, the following C statement consists of five tokens:        printf("Hello, World! \n"); 1.printf 2.( 3."Hello, World! \n" 4.) 5.;(semicolon) Let Us Describe about these Tokens One By One:- A.) Semicolons:- the semicolon is a statement terminator. That is, each individual statement must be ended with a semicolon. It indicates the end of one logical entity. For Example: printf("Helo"); getch(); Given Above Is Example Of Termination Of Two Statements. B.)Comments:- Comments are like helping text in your C program and they are ignored by the compiler. They start with /* and terminate with the characters */ as shown below: /*This Is My First Program*/        OR We can use double slash(//) for comment one line as:- //this is My First Program C.) Identifiers:- A C identifier is a name used ...
Post a Comment
Read more

Operators In C Language

About Operator:- *An operator is a symbol that tells the compiler to perform specific mathematical or logical functions. *C language is rich in built-in operators and provides the   following types of operators:- 1)Arithmetic Operators 2) Relational Operators 3) Logical Operators 4) Bitwise Operators 5) Assignment Operators 6) Misc Operator s  Now We Look All Oprators One By One:- 1)Airthmatic Operators: The List Of Operators And Their Description As Well As Example Is Given In Below Table We Assume Value Of A=10 And B=20 Example Program:-                                                       #include <stdio.h> int main() {                                                               ...
Post a Comment
Read more