public member function
<list>

std::list::erase

iterator erase (iterator position);
iterator erase (iterator first, iterator last);
iterator erase (const_iterator position);
iterator erase (const_iterator first, const_iterator last);
Erase elements
Removes from the list container either a single element (position) or a range of elements ([first,last)).

This effectively reduces the container size by the number of elements removed, which are destroyed.

Unlike other standard sequence containers, list and forward_list objects are specifically designed to be efficient inserting and removing elements in any position, even in the middle of the sequence.

Parameters

position
Iterator pointing to a single element to be removed from the list.
Member types iterator and const_iterator are bidirectional iterator types that point to elements.
first, last
Iterators specifying a range within the list] to be removed: [first,last). i.e., the range includes all the elements between first and last, including the element pointed by first but not the one pointed by last.
Member types iterator and const_iterator are bidirectional iterator types that point to elements.

Return value

An iterator pointing to the new location of the element that followed the last element erased by the function call. This is the container end if the operation erased the last element in the sequence.

Member type iterator is a bidirectional iterator type that points to elements.

Example

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// erasing from list
#include <iostream>
#include <list>

int main ()
{
  std::list<int> mylist;
  std::list<int>::iterator it1,it2;

  // set some values:
  for (int i=1; i<10; ++i) mylist.push_back(i*10);

                              // 10 20 30 40 50 60 70 80 90
  it1 = it2 = mylist.begin(); // ^^
  advance (it2,6);            // ^                 ^
  ++it1;                      //    ^              ^

  it1 = mylist.erase (it1);   // 10 30 40 50 60 70 80 90
                              //    ^           ^

  it2 = mylist.erase (it2);   // 10 30 40 50 60 80 90
                              //    ^           ^

  ++it1;                      //       ^        ^
  --it2;                      //       ^     ^

  mylist.erase (it1,it2);     // 10 30 60 80 90
                              //        ^

  std::cout << "mylist contains:";
  for (it1=mylist.begin(); it1!=mylist.end(); ++it1)
    std::cout << ' ' << *it1;
  std::cout << '\n';

  return 0;
}

Output:
mylist contains: 10 30 60 80 90

Complexity

Linear in the number of elements erased (destructions).

Iterator validity

Iterators, pointers and references referring to elements removed by the function are invalidated.
All other iterators, pointers and references keep their validity.

Data races

The container is modified.
The elements removed are modified. Concurrently accessing or modifying other elements is safe, although iterating ranges that include the removed elements is not.

Exception safety

If position (or the range) is valid, the function never throws exceptions (no-throw guarantee).
Otherwise, it causes undefined behavior.

See also