std::deque::front

 

C++

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Regular expressions library (C++11)

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Containers library

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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 front();
const_reference front() const;

Returns a reference to the first element in the container.

Parameters

(none)

Return value

reference to the first element

Complexity

Constant

Example

The following code uses front to display the first element of a std::deque<char>:

#include <deque>
#include <iostream>
 
int main()
{
    std::deque<char> letters {'o', 'm', 'g', 'w', 't', 'f'};
 
    if (!letters.empty()) {
        std::cout << "The first character is: " << letters.front() << '\n';
    }  
}

Output:

The first character is o

See also

back	access the last element (public member function)