I am new to c++ programming and trying to understand this syntax
int **arr;
arr = new int *[5];
I am confused about this part new int *[5]; Does it mean pointer of type int to 5 subpointers?
Any help will be appreciated.
3 Answers
This will hopefully become clear when you read it piece by piece:
new int * [5]
^^^ ^^^^^ ^^^
give me pointers to int and five of those.
Then you safe the address of the first of the new pointers in arr and thus have an dynamically allocated array of five pointers.
Note that "in the real world" (i.e. if no teacher/prof forbids you to) you would use an std::vector instead of new[].
answered Jul 16, 2015 at 19:59
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You are declaring an array of pointers to integers.
The array capacity is 5 (pointers).
The variable is allocated in dynamic memory because of new.
answered Jul 16, 2015 at 19:59
Thomas Matthews
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When you have problem with a non trivial type use typedef (at least in your head):
typedef int* int_ptr;
int_ptr *arr;
arr = new int_ptr[5];
It is easier to understand now, is it not?
Does it mean pointer of type int to 5 subpointers?More like a pointer of type "int pointer", and a 5 element array with that.