What is the difference between a static and a dynamic linked list?

A static linked list and a dynamic linked list are two different implementations of linked lists, which are data structures used to store and manipulate collections of elements.

1. Static Linked List:
A static linked list is implemented using an array. In a static linked list, the memory for the list is allocated at compile-time and remains fixed throughout the program execution. It means that the size of the list is predetermined and cannot be changed dynamically during runtime. Each element in the list contains a data value and a pointer to the next element in the list. The last element of the list points to a special value (usually NULL) to indicate the end of the list.

Advantages of Static Linked List:
- Efficient memory usage as the memory is allocated in a contiguous block.
- Random access is possible as elements are stored in an array.
- Simplicity in implementation.

Disadvantages of Static Linked List:
- Limited size as the size is fixed at compile-time.
- Inefficient memory usage if the list size is smaller than the allocated memory.
- Insertion and deletion operations are time-consuming as shifting of elements is required.

2. Dynamic Linked List:
A dynamic linked list is implemented using pointers. In a dynamic linked list, the memory for each element is allocated dynamically during runtime using the "malloc" or "new" function. It means that the size of the list can be changed dynamically by adding or removing elements. Each element in the list contains a data value and a pointer to the next element in the list. The last element of the list points to NULL to indicate the end of the list.

Advantages of Dynamic Linked List:
- Dynamic size allows flexibility in adding or removing elements.
- Efficient memory usage as memory is allocated only when needed.
- Insertion and deletion operations are relatively faster as no shifting of elements is required.

Disadvantages of Dynamic Linked List:
- Extra memory overhead due to the storage of pointers.
- Random access is not possible as elements are not stored in a contiguous block.
- Complexity in implementation due to the need for managing memory allocation and deallocation.

In summary, the main difference between a static and a dynamic linked list lies in the memory allocation. A static linked list has a fixed size allocated at compile-time, while a dynamic linked list allows for dynamic resizing during runtime.