public member function

std::list::push_front

<list>
void push_front ( const T& x );
Insert element at beginning
Inserts a new element at the beginning of the list, right before its current first element. The content of this new element is initialized to a copy of x.

This effectively increases the list size by one.

Parameters

x
Value to be copied to the new element.
T is the first template parameter (the type of the elements stored in the container).

Return value

none

The storage for the new element is allocated using Allocator::allocate(), which may throw exceptions on failure (for the default allocator, bad_alloc is thrown if the allocation request does not succeed).

Example

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// list::push_front
#include <iostream>
#include <list>
using namespace std;

int main ()
{
  list<int> mylist (2,100);         // two ints with a value of 100
  mylist.push_front (200);
  mylist.push_front (300);

  cout << "mylist contains:";
  for (list<int>::iterator it=mylist.begin(); it!=mylist.end(); ++it)
    cout << " " << *it;

  cout << endl;
  return 0;
}


Output:
300 200 100 100

Complexity

Constant.

See also

list::push_back
Add element at the end (public member function)
list::pop_front
Delete first element (public member function)
list::insert
Insert elements (public member function)

C++