What is the difference between pointer and iterator in C programming?

Pointers and iterators both allow you to access elements within data structures, but they differ in their implementation and capabilities.

Pointers:

• Direct Memory Access: Pointers directly store memory addresses, allowing you to manipulate data at specific locations in memory.
• Low-Level Control: Pointers provide fine-grained control over memory management, enabling tasks like dynamic memory allocation and data manipulation at the byte level.
• Flexibility: Pointers can be used with various data types and can be manipulated to access elements in different ways.

Iterators:

• Abstract Interface: Iterators are objects that provide a standardized interface for traversing through data structures. They abstract the underlying memory management details.
• Container-Specific: Iterators are tailored to specific data structures like arrays, lists, or trees, providing methods for accessing and manipulating elements within the container.
• Safety: Iterators often incorporate safety mechanisms, such as bounds checking, to prevent accessing invalid memory locations.

Example:

Let's consider accessing elements in an array:

Pointer Approach:

int arr[5] = {1, 2, 3, 4, 5};
int *ptr = arr; // Pointer pointing to the first element of the array

for (int i = 0; i < 5; i++) {
    printf("%d ", *ptr); // Accessing the element using the pointer
    ptr++; // Incrementing the pointer to point to the next element
}

Iterator Approach:

std::vector<int> v = {1, 2, 3, 4, 5};
std::vector<int>::iterator it = v.begin(); // Iterator pointing to the beginning of the vector

for (; it != v.end(); ++it) {
    std::cout << *it << " "; // Accessing the element using the iterator
}

In this example, both the pointer and iterator approaches achieve the same outcome – iterating through the array and printing its elements. However, the iterator approach provides a more abstract and safer way to traverse the container.

Key Differences: