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Simple questions. How does the STL list locate an element at a specified position?

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Post time: 2020-1-31 09:00:02
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For example, I want to get the 7th element in the list from begin. How can I get this?
Please give an example!
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Post time: 2020-3-23 12:15:01
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typedef yourtype ltype;
std :: list <ltype> yourlist;
typedef std :: list <ltype> :: iterator pos = yourlist.begin ();
for (unsigned int i = 0; pos! = yourlist.end (); pos ++)
{
  i ++;
  if (i == 7)
    break;
}
if (i == 7)
  ltype lt = * pos;

Where yourtype is your type in the list
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Post time: 2020-3-23 14:15:01
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As for yourlist is your list variable
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Post time: 2020-3-26 19:15:02
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You can use iterators directly at specified positions ++
for (it = mylist.begin (), i = 0; it! = mylist.end (); it ++, i ++)
{
    if (i> 6)
        break;
}
if (i == 7)
{...} // found
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