list::push_front
public member function
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
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
|
// 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:
Complexity
Constant.
See also
|