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C Exercises: How to handle the pointers in the program


2. Pointer Handling Demonstration

Write a program in C to demonstrate how to handle pointers in a program..

Visual Presentation:

C Exercises: Pictorial: How to handle the pointers in the program .

Sample Solution:

C Code:

#include <stdio.h>

int main()
{
    int* ab; // Declare a pointer variable ab
    int m;   // Declare an integer variable m

    m = 29; // Assign the value 29 to the variable m

    printf("\n\n Pointer : How to handle the pointers in the program :\n");
    printf("------------------------------------------------------------\n");
    printf(" Here in the declaration ab = int pointer, int m = 29\n\n");

    printf(" Address of m : %p\n", &m); // Print the address of variable m
    printf(" Value of m : %d\n\n", m); // Print the value of variable m

    ab = &m; // Assign the address of m to the pointer variable ab

    printf(" Now ab is assigned with the address of m.\n");
    printf(" Address of pointer ab : %p\n", ab);      // Print the address stored in pointer ab
    printf(" Content of pointer ab : %d\n\n", *ab);   // Print the value pointed to by ab

    m = 34; // Assign the value 34 to the variable m

    printf(" The value of m assigned to 34 now.\n");
    printf(" Address of pointer ab : %p\n", ab);      // Print the address stored in pointer ab
    printf(" Content of pointer ab : %d\n\n", *ab);   // Print the value pointed to by ab

    *ab = 7; // Assign the value 7 to the variable pointed by ab

    printf(" The pointer variable ab is assigned the value 7 now.\n");
    printf(" Address of m : %p\n", &m);               // Print the address of variable m
                                                      // as ab contains the address of m
                                                      // *ab changed the value of m and now m becomes 7
    printf(" Value of m : %d\n\n", m);                // Print the value of variable m

    return 0;
}

Sample Output:

 Pointer : How to  handle the pointers in the program :                                                       
------------------------------------------------------------                                                  
 Here in the declaration ab = int pointer, int m= 29                                                          
                                                                                                              
 Address of m : 0x7fff24a3f8bc                                                                                
 Value of m : 29                                                                                              
                                                                                                              
 Now ab is assigned with the address of m.                                                                    
 Address of pointer ab : 0x7fff24a3f8bc                                                                       
 Content of pointer ab : 29                                                                                   
                                                                                                              
 The value of m assigned to 34 now.                                                                           
 Address of pointer ab : 0x7fff24a3f8bc                                                                       
 Content of pointer ab : 34                                                                                   
                                                                                                              
 The pointer variable ab is assigned the value 7 now.                                                         
 Address of m : 0x7fff24a3f8bc                                                                                
 Value of m : 7 

Flowchart:

Flowchart: How to  handle the pointers in the program

For more Practice: Solve these Related Problems:

  • Write a C program to assign a pointer with the address of a variable, change the variable’s value, and display the pointer’s dereferenced value before and after the change.
  • Write a C program to demonstrate pointer reassignment by assigning a pointer to different variables sequentially and printing their addresses and values.
  • Write a C program to show how pointer values change when the pointed variable is modified using direct assignment and pointer dereferencing.
  • Write a C program to swap the values of two variables using a pointer and then display the updated values along with their addresses.

Go to:


PREV : Basic Pointer Declaration.
NEXT : Use of & and * Operators.

C Programming Code Editor:



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