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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

#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)

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