返回子列表c ++的迭代器

Question

We have a list

std::list<int> list;

// fill part of the list with 5
list.push_back(5);
list.push_back(5);
list.push_back(5);

// fill part of the list with 10
list.push_back(10);
list.push_back(10);
list.push_back(10);

// iterator that starts with 5
std::list<int>::iterator iterFiveBegin = list.begin();


//
std::list<int>::iterator iterEnd = list.end();

How can I get the iterator std::list<int>::iterator iterTenBegin of the list where it starts with "10"?

Answer 1

Firstly, don't use variable name list , try intList instead.

You may use std::find

std::list<int>::iterator it = std::find (intList.begin(), intList.end(), 10);

Per std::find documentation :

std::find
Return value
Iterator to the first element satisfying the condition or last if no such element is found.

Answer 2

Just use std::find , from the <algorithm> header:

std::list<int>::const_iterator ten = std::find(list.begin(), list.end(), 10);

Make sure to check that it is valid:

if (ten == list.end())
{
  // no 10 found in list
}

Also, don't name your std::list instance "list".

Answer 3

如果您的列表已排序，我想您可以使用std :: lower_bound和std :: upper_bound