Question

I have the below code:

int* d = (int*) malloc(100 * sizeof(int));
cout<<"size of d which is pointer is: " << sizeof(d)<<endl;

I know that sizeof outputs 4 as d is a ptr. But, how can I find the sizeof the entire array using sizeof

Answer 1

You cannot – sizeof is a compile time operation and hence not dynamic.

As you are using c++ use std::vector instead. Otherwise create a structure to store both the pointer and the size of the array. Pass that around instead.