C++ List Library - list() Function

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Description

The C++ range constructor std::list::list() constructs a list with as many elements as in range of first to last.

Declaration

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

C++98

list (InputIterator first, InputIterator last,
      const allocator_type& alloc = allocator_type());

C++11

list (InputIterator first, InputIterator last,
      const allocator_type& alloc = allocator_type());

Parameters

• first − Input iterator to initial position.

• last − Input iterator to final position.

• alloc − Allocator object.

Return value

Constructor never returns value.

Exceptions

If range specified by first and last is not valid then result is undefined.

Time complexity

Linear i.e. O(n)

Example

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

#include <iostream>
#include <list>

using namespace std;

int main(void) {
   list<int> l1 = {1, 2, 3, 4, 5};
   list<int> l2(l1.begin(), l1.end());

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

   for (auto it = l2.begin(); it != l2.end(); ++it)
      cout << *it << endl;

   return 0;
}

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

List contains following element
1
2
3
4
5