Memory Management in C++

What is Memory Management in C++?

It allocates memory for a variable or array during runtime. This is referred to as dynamic memory allocation. Manually deallocate dynamically allocated RAM when no longer needed. Memory can be dynamically allocated and deallocated using the new and delete operators.

Need for Memory Management

Memory management is necessary to prevent memory waste and ensure optimal allocation. A C++ program's memory is separated into multiple parts.

• Stack: The stack stores all of the variables defined inside the function as well as other function-related information.
• Heap: Heap is unused memory that is dynamically allocated as the program runs. 

Allocation & Deallocation of Memory 

In C++, allocation and deallocation are performed manually. C++ uses two operators for memory allocation and deallocation, i.e.

• new operator
• delete operator

C++ New Operator

The C++ new operator can be used to allocate memory at runtime. The new operator in C++ is used for dynamic memory allocation; it allocates memory on the heap at runtime.

C++ delete operator

Once memory has been allocated, we can delete it when it is no longer required. The delete operator in C++ is used to deallocate memory. When we no longer need to utilize the variable, which indicates that the memory is no longer needed, we must deallocate or release it using the delete operator.

Why Do We Use Dynamic Memory Allocation?

Dynamic memory allocation has various advantages, including:

• Flexibility: With dynamic memory allocation, we can allocate RAM as needed during runtime. This flexibility is useful when the size of data structures is unknown at compile time or varies during program execution.
• Data Structures: Data structures such as linked lists, trees, graphs, and resizable arrays (vectors in C++) frequently require dynamic memory allocation to handle variable amounts of data.
• Resource Management: Memory can be allocated and deallocated as needed. This results in greater resource use.
• Dynamic Arrays: In languages such as C++, static arrays have fixed widths that are determined at build time. Dynamic memory allocation enables us to design arrays whose sizes can be determined at runtime.