std::unique_ptr<T,Deleter>:: operator[]

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Utilities library
General utilities
Relational operators (deprecated in C++20)
Dynamic memory management
Uninitialized memory algorithms
Constrained uninitialized memory algorithms
Allocators
Garbage collection support
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)
(C++11) (until C++23)



T & operator [ ] ( std:: size_t i ) const ;
(since C++11)
(constexpr since C++23)

operator[] provides access to elements of an array managed by a unique_ptr .

The parameter i shall be less than the number of elements in the array; otherwise, the behavior is undefined.

This member function is only provided for specializations for array types.

Parameters

i - the index of the element to be returned

Return value

Returns the element at index i , i.e. get()[i] .

Example

#include <iostream>
#include <memory>
 
int main() 
{
    const int size = 10; 
    std::unique_ptr<int[]> fact(new int[size]);
 
    for (int i = 0; i < size; ++i)
        fact[i] = (i == 0) ? 1 : i * fact[i - 1];
 
    for (int i = 0; i < size; ++i)
        std::cout << i << "! = " << fact[i] << '\n';
}

Output:

0! = 1
1! = 1
2! = 2
3! = 6
4! = 24
5! = 120
6! = 720
7! = 5040
8! = 40320
9! = 362880

See also

returns a pointer to the managed object
(public member function)