C++ List Library - insert() Function

Description

The C++ function std::list::insert() extends iterator by inserting new element at position in list. This member function increases size of the list.

Declaration

Following is the declaration for std::list::insert() function form std::list header.

C++98

iterator insert (iterator position, const value_type& val);

C++11

iterator insert (const_iterator position, const value_type& val);

Parameters

• position − Position in the list where new element to be inserted.

• val − Value to be assigned to newly inserted element.

Return value

Returns a random access iterator which points to the newly inserted element.

Exceptions

If reallocation fails bad_alloc exception is thrown.

Time complexity

Linear i.e. O(n)

Example

The following example shows the usage of std::list::insert() function.

#include <iostream>
#include <list>

using namespace std;

int main(void) {
   list<int> l;

   for (int i = 0; i < 5; ++i)
      l.insert(l.end(), i + 1);

   cout << "List contains following elements" << endl;

   for (auto it = l.begin(); it != l.end(); ++it)
      cout << *it << endl;

   return 0;
}

Let us compile and run the above program, this will produce the following result −

List contains following elements
1
2
3
4
5