How does memory allocation differ for static and dynamic structures?

Static structures have fixed memory allocation at compile time, while dynamic structures have memory allocated at runtime.

In more detail, static structures are those where the memory size is known at compile time. This means that the amount of memory needed is determined before the program is run. This is often used for arrays and other data structures where the size is known in advance. The memory for these structures is allocated on the stack, which is a region of memory that is automatically managed by the compiler. The advantage of static memory allocation is that it is fast and there is no risk of memory leaks, as the compiler automatically frees up the memory when it is no longer needed. However, the downside is that the size of the structure cannot be changed once it is defined, which can lead to wasted memory if the structure is not fully utilised.

On the other hand, dynamic structures have their memory allocated at runtime. This means that the amount of memory needed is determined while the program is running. This is often used for data structures where the size is not known in advance, such as linked lists and trees. The memory for these structures is allocated on the heap, which is a region of memory that is manually managed by the programmer. The advantage of dynamic memory allocation is that it allows for more flexibility, as the size of the structure can be changed as needed. However, it is slower than static memory allocation and there is a risk of memory leaks if the programmer forgets to free up the memory when it is no longer needed.

In summary, static and dynamic structures differ in when and how their memory is allocated. Static structures have their memory allocated at compile time on the stack, while dynamic structures have their memory allocated at runtime on the heap. Each method has its own advantages and disadvantages, and the choice between them depends on the specific requirements of the program.