C++ <deque> - pop_front() Function

The C++ deque::pop_front function is used to delete the first element of the deque. Every deletion of element results into reducing the container size by one unless the deque is empty.

Syntax

C++98
C++11

void pop_front();

void pop_front();

Parameters

No parameter is required.

Return Value

None.

Time Complexity

Constant i.e, Θ(1).

Example:

In the example below, the deque::pop_front function is used to delete the first element of the deque called MyDeque.

#include <iostream>
#include <deque>
using namespace std;
 
int main (){
  deque<int> MyDeque{100, 200, 300, 400, 500, 600};
  deque<int>::iterator it;

  //deletes first element of the deque
  MyDeque.pop_front();
  //deletes next first element of the deque
  MyDeque.pop_front();

  cout<<"The deque contains:";
  for(it = MyDeque.begin(); it != MyDeque.end(); ++it)
    cout<<" "<<*it;

  return 0;
}

The output of the above code will be:

The deque contains: 300 400 500 600

❮ C++ <deque> Library