sizeofarray

sizeofarray is a term used to describe the memory size, in bytes, occupied by an array’s contents in a given programming language. It is not a universal function name, but the concept appears in several languages in slightly different forms. The precise meaning depends on the language and on how the array is stored and passed around.

In C and C++, for a statically declared array, the operator sizeof yields the total size of the array in bytes. This equals the number of elements multiplied by the size of each element. For example, an array of 10 integers will have a total size of 10 * sizeof(int). A related calculation, to determine the number of elements, is sizeof(array) / sizeof(array[0]). However, when an array is passed to a function, it decays to a pointer, and sizeof no longer provides the array’s length or total storage. Dynamically allocated arrays (or pointers) also require separate tracking of length, since sizeof yields only the size of the pointer, not the allocated memory.

In modern C++, there are safer alternatives. std::size(array) yields the number of elements for fixed-size arrays, and std::vector stores its length in a dedicated size() method. For languages with managed runtimes, such as Java, there is no equivalent to sizeof for general memory usage. Java arrays expose a length field indicating element count, but their byte footprint is managed by the runtime and is not directly accessible.

Other languages vary: Python exposes length via len(), but the actual memory consumption includes overhead beyond the elements; sys.getsizeof reports object size but not the memory used by referenced objects. Understanding sizeofarray requires awareness of scope, storage duration, and language-specific memory models.