std::unique_ptr::operator[]

T& operator[](size_t i) const;		(since C++11)

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.

Parameters

i

-

the index of the element to be returned

Return value

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

Example

Run this code

#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:

Language
Standard Library Headers
Freestanding and hosted implementations
Named requirements
Language support library
Concepts library (C++20)
Diagnostics library
Utilities library
Strings library
Containers library
Iterators library
Ranges library (C++20)
Algorithms library
Numerics library
Input/output library
Localizations library
Regular expressions library (C++11)
Atomic operations library (C++11)
Thread support library (C++11)
Filesystem library (C++17)
Technical Specifications

Member functions
unique_ptr::unique_ptr
unique_ptr::~unique_ptr
unique_ptr::operator=
Modifiers
unique_ptr::release
unique_ptr::reset
unique_ptr::swap
Observers
unique_ptr::get
unique_ptr::get_deleter
unique_ptr::operator bool
unique_ptr::operator*unique_ptr::operator->
unique_ptr::operator[]
Non-member functions
make_uniquemake_unique_default_init (C++14)(C++20)
operator==operator!=operator<operator>operator<=operator>operator>=
operator<< (C++20)
std::swap
std::hash

std::unique_ptr::operator[]

Parameters

Return value

Example

See also

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