sorting std::lists using std::sort

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Sort list using stl sort function

My question is can we sort two std::lists using std::sort function? I have 2 string lists

  std::list<std::string>list1, list2;
  .....//entering values to list
  std::sort(list1.begin(), list1.end());

  std::sort(list2.begin(), list2.end());

while i am sorting these lists i am getting error. I tried with std::vector, at this time the sort works.

The error is like

C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\include\xutility(1158) : see declaration of 'std::operator -' 1>C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\include\algorithm(3642): error C2784: '_Base1::difference_type std::operator - (const std::_Revranit<_RanIt,_Base> &,const std::_Revranit<_RanIt2,_Base2> &)' : could not deduce template argument for 'const std::_Revranit<_RanIt,_Base> &' from 'std::_List_iterator<_Mylist>' 1> with 1> [ 1> _Mylist=std::_List_valstd::string,std::allocator<std::string> 1> ]

I have to know that only std::sort supports lists?

Overload the < operator for your object (if it's not already defined) and use std::sort. — Martol1ni, May 18 '12 at 12:31
possible duplicate of [why only std::list::sort()?](http://stackoverflow.com/questions/7996116/why-only-stdlistsort) and [Sort list using stl sort function](http://stackoverflow.com/questions/2432857/sort-list-using-stl-sort-function) — JoeG, May 18 '12 at 12:32
@Martol1ni: It's `std::string`. `operator<` is defined, but it won't help. — Benjamin Lindley, May 18 '12 at 12:33

score 60 · Accepted Answer · answered May 18 '12 at 12:30

You can't use std::sort to sort std::list, because std::sort requires iterators to be random access, and std::list iterators are only bidirectional.

However, std::list has a member function sort that will sort it:

list.sort();
// if you want to use a comparator different from the default one:
// list.sort(comparator);

Potatoswatter · Answer 2 · 2016-01-17T03:42:58.007

You should use list::sort, which may use a different algorithm. std::sort requires random-access iterators (supporting jumps of arbitrary size) whereas list iterators can only go forwards or backwards by one link at a time.

See C++11 25.4.1.1:

template<class RandomAccessIterator> void sort(RandomAccessIterator first, 
         RandomAccessIterator last);

and 23.3.5.5/27 (members of std::list):

void sort();
template <class Compare> void sort(Compare comp);

sorting std::lists using std::sort

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