std::deque pop_back() method

since C++98

// Non const version only
void pop_back();

Removes the first element of the container.

Undefined Behavior

Calling pop_front on an empty container results in undefined behavior

.

since C++11

Invalidation

Iterators and references to the erased element are invalidated.
The past-the-end iterator is also invalidated.
Other references and iterators are not affected.

until C++11

Invalidation

Iterators and references to the erased element are invalidated.
It is unspecified whether the past-the-end iterator is invalidated.
Other references and iterators are not affected.

Parameters

(none)

Return value

(none)

Complexity

Constant - O(1).

Exceptions

(none)

Example

Main.cpp

#include <deque>
#include <iostream>
 
int main()
{
    std::deque<char> chars{'A', 'B', 'C', 'D'};
 
    for (; !chars.empty(); chars.pop_front())
    {
        std::cout << "chars.front(): '" << chars.front() << "'\n";
    }
}

Output

chars.front(): 'A'
chars.front(): 'B'
chars.front(): 'C'
chars.front(): 'D'