c++ - Is it useful to create pointer(s) on the heap? -

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is useful create pointer or array of pointers on heap ? if when , why need ?

for example: 

#include <iostream>  class box { /*  things... */ };  int main(void){      // single pointer on heap     box** pbox = new box*(nullptr);     *pbox = new box();      // array of pointers on heap     box** pboxes = new box*[3]{};     pboxes[0] = new box();     pboxes[1] = new box();     pboxes[2] = new box();      // delete pointers...      return 0; }

edit: make question more clear ... know dealing raw pointers not best practice ... want understand pointers , uses important part of c++ hence question (is useful...).

the reasoning behind allocating memory space on heap or on stack not related type of variables allocated, it's related how it's allocated , how it's meant used.

in case, nowadays should avoid new statements , use "managed" pointers, particularly std::xxx variants.


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