C programming tutorials for Beginners – C structs and Pointers

(C Programming Tutorials)

C structs and Pointers

In this tutorial, you’ll learn to use pointers to access members of structs in C programming. You will also learn to dynamically allocate memory of struct types.

  • C Pointers
  • C struct

C Pointers to struct

Here’s how you can create pointers to structs.

struct name {

int main(){
    struct name *ptr, Harry;

Here, ptr is a pointer to struct.

Example: Access members using Pointer

To access members of a structure using pointers, we use the -> operator.

#include <stdio.h>
struct person
   int age;
   float weight;

int main(){
    struct person *personPtr, person1;
    personPtr = &person1;   

    printf("Enter age: ");
    scanf("%d", &personPtr->age);

    printf("Enter weight: ");
    scanf("%f", &personPtr->weight);

    printf("Age: %dn", personPtr->age);
    printf("weight: %f", personPtr->weight);

    return 0;

In this example, the address of person1 is stored in the personPtr pointer using personPtr = &person1;.

Now, you can access the members of person1 using the personPtr pointer.

By the way,

  • personPtr->age is equivalent to (*personPtr).age
  • personPtr->weight is equivalent to (*personPtr).weight

Dynamic memory allocation of structs

Before you proceed this section, we recommend you to check C dynamic memory allocation.

Sometimes, the number of struct variables you declared may be insufficient. You may need to allocate memory during run-time. Here’s how you can achieve this in C programming.

Example: Dynamic memory allocation of structs

#include <stdio.h>
#include <stdlib.h>
struct person {
   int age;
   float weight;
   char name[30];

int main(){
   struct person *ptr;
   int i, n;

   printf("Enter the number of persons: ");
   scanf("%d", &n);

   // allocating memory for n numbers of struct person
   ptr = (struct person*) malloc(n * sizeof(struct person));

   for(i = 0; i < n; ++i)
       printf("Enter first name and age respectively: ");

       // To access members of 1st struct person,
       // ptr->name and ptr->age is used

       // To access members of 2nd struct person,
       // (ptr+1)->name and (ptr+1)->age is used
       scanf("%s %d", (ptr+i)->name, &(ptr+i)->age);

   printf("Displaying Information:n");
   for(i = 0; i < n; ++i)
       printf("Name: %stAge: %dn", (ptr+i)->name, (ptr+i)->age);

   return 0;

When you run the program, the output will be:

Enter the number of persons:  2
Enter first name and age respectively:  Harry 24
Enter first name and age respectively:  Gary 32
Displaying Information:
Name: Harry	Age: 24
Name: Gary	Age: 32

In the above example, n number of struct variables are created where n is entered by the user.

To allocate the memory for n number of struct person, we used,

ptr = (struct person*) malloc(n * sizeof(struct person));

Then, we used the ptr pointer to access elements of person.


Personal Career & Learning Guide for Data Analyst, Data Engineer and Data Scientist

Applied Machine Learning & Data Science Projects and Coding Recipes for Beginners

A list of FREE programming examples together with eTutorials & eBooks @ SETScholars

95% Discount on “Projects & Recipes, tutorials, ebooks”

Projects and Coding Recipes, eTutorials and eBooks: The best All-in-One resources for Data Analyst, Data Scientist, Machine Learning Engineer and Software Developer

Topics included: Classification, Clustering, Regression, Forecasting, Algorithms, Data Structures, Data Analytics & Data Science, Deep Learning, Machine Learning, Programming Languages and Software Tools & Packages.
(Discount is valid for limited time only)

Disclaimer: The information and code presented within this recipe/tutorial is only for educational and coaching purposes for beginners and developers. Anyone can practice and apply the recipe/tutorial presented here, but the reader is taking full responsibility for his/her actions. The author (content curator) of this recipe (code / program) has made every effort to ensure the accuracy of the information was correct at time of publication. The author (content curator) does not assume and hereby disclaims any liability to any party for any loss, damage, or disruption caused by errors or omissions, whether such errors or omissions result from accident, negligence, or any other cause. The information presented here could also be found in public knowledge domains.

Learn by Coding: v-Tutorials on Applied Machine Learning and Data Science for Beginners

Please do not waste your valuable time by watching videos, rather use end-to-end (Python and R) recipes from Professional Data Scientists to practice coding, and land the most demandable jobs in the fields of Predictive analytics & AI (Machine Learning and Data Science).

The objective is to guide the developers & analysts to “Learn how to Code” for Applied AI using end-to-end coding solutions, and unlock the world of opportunities!


C programming tutorials for Beginners – C structure

C programming tutorials for Beginners – C Structure and Function

C Example for Beginners: C Program to Find Largest Number Using Dynamic Memory Allocation