# std::deque<T,Allocator>::pop_front

From cppreference.com
< cpp‎ | container‎ | deque

void pop_front(); |  |

Removes the first element of the container. If there are no elements in the container, the behavior is undefined.

Iterators and references to the erased element are invalidated. If the element is the last element in the container, the end() iterator is also invalidated. Other references and iterators are not affected.

### Parameters

(none)

### Return value

(none)

### Complexity

Constant.

### Exceptions

Does not throw.

### Example

Run this code

    #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'

### See also

pop_back | removes the last element (public member function)
push_front | inserts an element to the beginning (public member function)
front | access the first element (public member function)

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