std::deque::operator[]

 

C++

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Concepts

Utilities library

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Containers library

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Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

 

Containers library

array (C++11)

vector

deque

forward_list (C++11)

list

set

multiset

map

multimap

unordered_set (C++11)

unordered_multiset (C++11)

unordered_map (C++11)

unordered_multimap (C++11)

stack

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std::deque

Member functions

deque::deque

deque::~deque

deque::operator=

deque::assign

deque::get_allocator

Element access

deque::front

deque::back

Iterators

deque::begin deque::cbegin (C++11)

deque::end deque::cend (C++11)

deque::rbegin deque::crbegin (C++11)

deque::rend deque::crend (C++11)

Capacity

deque::empty

deque::size

deque::max_size

deque::shrink_to_fit

Modifiers

deque::clear

deque::insert

deque::emplace

deque::erase

deque::push_front

deque::emplace_front

deque::pop_front

deque::push_back

deque::emplace_back

deque::pop_back

deque::resize

deque::swap

 

reference       operator[]( size_type pos );
const_reference operator[]( size_type pos ) const;

Returns a reference to the element at specified location pos. No bounds checking is performed.

Parameters

pos

-

position of the element to return

Return value

reference to the requested element

Complexity

Constant

Example

The following code uses operator[] read from and write to a std::deque<int>:

#include <deque>
#include <iostream>
 
int main()
{
    std::deque<int> numbers {2, 4, 6, 8};
 
    std::cout << "Second element: " << numbers[1] << '\n';
 
    numbers[0] = 5;
 
    std::cout << "All numbers:";
    for (auto i : numbers) {
        std::cout << ' ' << i;
    }
    std::cout << '\n';
}

Output:

Second element: 4
All numbers: 5 4 6 8

See also

at	access specified element with bounds checking (public member function)