How to Create a Dynamic Array Inside a Structure?

In C, the structure can store the array data types as one of its members. In this article, we will learn how to create a dynamic array inside a structure in C.

Creating a Dynamic Array Inside a Structure in C

To create a dynamic array inside a structure in C, define a structure that contains a pointer to the array type and a variable to store the size of the array. Then initialize the dynamic array with that size using malloc() to dynamically allocate memory for the array.

Syntax to Create a Dynamic Array Inside a Structure

// Define the structure
struct StructName {
    dataType* arrayName;
    int size;
};

// In function 
StructName variableName;
variableName.arrayName = new dataType[size];
variableName.size = size;

Here,

• StructName is the name of the structure.
• dataType is the type of data that the array holds
• arrayName is the name of the array.
• variableName is the name of the structure variable.
• size is the size of the array.

C++ Program to Create a Dynamic Array Inside a Structure

The below program demonstrates how we can create a dynamic array inside a structure in C++.

// C Program to illustrate how to create a dynamic array
// inside a structure
#include <stdio.h>
#include <stdlib.h>

// Define the structure
typedef struct myStruct {
    int* myArray;
    int size;
} MyStruct;

int main()
{
    // Define the size of the array
    int size = 5;

    // Create a structure variable
    MyStruct s;

    // Create a dynamic array inside the structure
    s.myArray = (int*)malloc(sizeof(int) * size);
    s.size = size;

    // Initialize the array
    for (int i = 0; i < size; i++) {
        s.myArray[i] = i;
    }

    // Print the array elements
    for (int i = 0; i < size; i++) {
        printf("%d ", s.myArray[i]);
    }

    // Delete the dynamic array
    free(s.myArray);

    return 0;
}

0 1 2 3 4 

Time Complexity: O(N), here N is the size of the array.
Auxiliary Space: O(N)