c++ - Dynamically allocating array of objects like int -

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in order create array of ints dynamically, need int *a = new int[20];.

is there similar way create array of objects or structs?

for example, need dynamically allocated array of objects of class a, how should declare it(syntax)?

what constructor called on each object(if @ constructor called)?

you can using line:

a* = new a[n];

how works?

the new keyword allocate n sequential block in heap. each block has size of sizeof(a) total size in bytes n*sizeof(a). allocating objects in memory ensured done calling default constructor n times.

alternative:

use std::vector instead. work you.


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