c++ - Confused with pointer and double pointer in the heap -

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i'm getting confused pointers , double pointers.

suppose have these

int* ptr = new int[2];

here, ptr has address of array of size 2 in heap keeps int data right?

int** ptr = new int* [2];

here, ptr has address 2 pointers in heap , these 2 pointers can point int data.

is thinking here correct?

this correct: in first case assign pointer memory block in heap sufficient storing 2 ints, can considered int array of size two.

the second ptr assigned pointer memory block in heap sufficient storing 2 pointers int. however, these pointers not point in particular until assign them value*, in same way assign other pointers. example, can make second ptr make array of 2 int arrays, this:

int** ptr = new int* [2]; ptr[0] = new int[2]; ptr[1] = new int[2];

* same true ints first code snippet: value indeterminate until assign them.


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