public member function
<list>

std::list::begin

      iterator begin();
const_iterator begin() const;
      iterator begin() noexcept;
const_iterator begin() const noexcept;
Return iterator to beginning
Returns an iterator pointing to the first element in the list container.

Notice that, unlike member list::front, which returns a reference to the first element, this function returns a bidirectional iterator pointing to it.

If the container is empty, the returned iterator value shall not be dereferenced.

Parameters

none

Return Value

An iterator to the beginning of the sequence container.

If the list object is const-qualified, the function returns a const_iterator. Otherwise, it returns an iterator.

Member types iterator and const_iterator are bidirectional iterator types (pointing to an element and to a const element, respectively).

Example

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// list::begin
#include <iostream>
#include <list>

int main ()
{
  int myints[] = {75,23,65,42,13};
  std::list<int> mylist (myints,myints+5);

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

  std::cout << '\n';

  return 0;
}


Output:
mylist contains: 75 23 65 42 13

Complexity

Constant.

Iterator validity

No changes.

Data races

The container is accessed (neither the const nor the non-const versions modify the container).
No contained elements are accessed by the call, but the iterator returned can be used to access or modify elements. Concurrently accessing or modifying different elements is safe.

Exception safety

No-throw guarantee: this member function never throws exceptions.
The copy construction or assignment of the returned iterator is also guaranteed to never throw.

See also

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