problem with sizeof operator

Question

As i want to find array size dynamically in function, i used sizeof operator. But i got some unexpected result. here is one demo program to show you, what i want to do.

Answer 1

Inside getSize(), you're getting size of pointer, which is 8 bytes (since you're probably running 64-bit OS). In main(), you're getting size of array.

If you want to know array size, pass result of sizeof(S) as additional argument to getSize().

More alternatives would be using some container (like std::vector) or turning function into template function, as Nawaz proposed.