What Is Pointer in Data Structure With Example?

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Heather Bennett

In this tutorial, we will delve into the concept of pointers in data structures and explore their usage with examples.

Introduction to Pointers

A pointer is a variable that stores the memory address of another variable. It allows us to indirectly access and modify the value of the variable it points to. Pointers are commonly used in data structures to efficiently manage and manipulate memory.

Pointers are denoted by an asterisk (*) followed by the type of data they point to. For example, int* represents a pointer to an integer.

Example: Using a Pointer

Let’s illustrate the concept of pointers with a simple example:

```    ```
int number = 10; // Define an integer variable
int* p; // Declare a pointer variable

p = &number; // Assign the address of 'number' to 'p'

printf("Value of number: %d\n", number); // Output: 10
printf("Value stored in pointer p: %p\n", p); // Output: Memory address of 'number'
printf("Value pointed by pointer p: %d\n", *p); // Output: 10

*p = 20; // Modify the value using the pointer

printf("Modified value of number: %d\n", number); // Output: 20
```
```

In this example, we first declare an integer variable called ‘number’ and initialize it with a value of 10. Then, we declare a pointer variable ‘p’ using the int* syntax. We assign the address of ‘number’ to ‘p’ using the ampersand (&) operator.

We can access the value of ‘number’ indirectly through the pointer by dereferencing it using the asterisk (*) operator. In the example, we print both the memory address of ‘number’ and the value stored in ‘p’. Notice how both values are the same.

Finally, we modify the value of ‘number’ by assigning a new value to ‘*p’. This change is reflected in ‘number’ as well since they share the same memory location.

Benefits of Using Pointers

Pointers offer several advantages when used in data structures:

• Efficient memory management: Pointers allow us to dynamically allocate and deallocate memory, enabling efficient usage of resources.
• Passing parameters by reference: Pointers enable functions to modify variables outside their scope by passing their addresses as arguments.
• Data structure implementation: Many data structures, such as linked lists and trees, rely heavily on pointers for efficient storage and manipulation of elements.

Conclusion

In conclusion, pointers play a crucial role in data structures by providing a means to access and manipulate memory indirectly. They offer benefits such as efficient memory management, passing parameters by reference, and facilitating data structure implementations. Understanding pointers is essential for any programmer looking to work with complex data structures efficiently.