제출 #477957

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
477957		omohamadooo	Combo (IOI18_combo)	C++14	컴파일 에러	0 ms	0 KiB

이 제출은 이전 버전의 oj.uz에서 채점하였습니다. 현재는 제출 당시와는 다른 서버에서 채점을 하기 때문에, 다시 제출하면 결과가 달라질 수도 있습니다.

combo

/*
      ___           ___           ___           ___           ___           ___           ___          _____          ___           ___           ___
     /  /\         /__/\         /  /\         /__/\         /  /\         /__/\         /  /\        /  /::\        /  /\         /  /\         /  /\
    /  /::\       |  |::\       /  /::\        \  \:\       /  /::\       |  |::\       /  /::\      /  /:/\:\      /  /::\       /  /::\       /  /::\
   /  /:/\:\      |  |:|:\     /  /:/\:\        \__\:\     /  /:/\:\      |  |:|:\     /  /:/\:\    /  /:/  \:\    /  /:/\:\     /  /:/\:\     /  /:/\:\
  /  /:/  \:\   __|__|:|\:\   /  /:/  \:\   ___ /  /::\   /  /:/~/::\   __|__|:|\:\   /  /:/~/::\  /__/:/ \__\:|  /  /:/  \:\   /  /:/  \:\   /  /:/  \:\
 /__/:/ \__\:\ /__/::::| \:\ /__/:/ \__\:\ /__/\  /:/\:\ /__/:/ /:/\:\ /__/::::| \:\ /__/:/ /:/\:\ \  \:\ /  /:/ /__/:/ \__\:\ /__/:/ \__\:\ /__/:/ \__\:\
 \  \:\ /  /:/ \  \:\~~\__\/ \  \:\ /  /:/ \  \:\/:/__\/ \  \:\/:/__\/ \  \:\~~\__\/ \  \:\/:/__\/  \  \:\  /:/  \  \:\ /  /:/ \  \:\ /  /:/ \  \:\ /  /:/
  \  \:\  /:/   \  \:\        \  \:\  /:/   \  \::/       \  \::/       \  \:\        \  \::/        \  \:\/:/    \  \:\  /:/   \  \:\  /:/   \  \:\  /:/
   \  \:\/:/     \  \:\        \  \:\/:/     \  \:\        \  \:\        \  \:\        \  \:\         \  \::/      \  \:\/:/     \  \:\/:/     \  \:\/:/
    \  \::/       \  \:\        \  \::/       \  \:\        \  \:\        \  \:\        \  \:\         \__\/        \  \::/       \  \::/       \  \::/
     \__\/         \__\/         \__\/         \__\/         \__\/         \__\/         \__\/                       \__\/         \__\/         \__\/

*/

#include "bits/stdc++.h"
#include "combo.h"
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define pb push_back
#define endl '\n'
#define pii pair<ll,ll >
#define F first
#define S second
#define ld long double

using namespace std;
//using namespace __gnu_pbds;

//typedef tree<ll , null_type , less_equal<ll> ,rb_tree_tag ,tree_order_statistics_node_update >ordered_set;

const int MOD=1e9+7;
const int  N=3e5+7;

long long po(ll x,ll y)
{
    ll ans=1;
    while(y){
        if(y & 1) ans=(ans*x);//%MOD;
        y/=2;
        x=(x*x);//%MOD;
    }
    return ans;
}

set<char>a;

string guess_sequence(int n)
{
    a.insert('A');
    a.insert('B');
    a.insert('X');
    a.insert('Y');
    string s="";
    for(ll i=1;i<=n;i++){
        bool f=0;
        for(set<char> :: iterator it=a.begin(); it!=a.end(); it++){
            if(it == a.rbegin()) break;
            if( press((string)(s+ *it])) == i){
                f=1;
                s+=*it;
                if(i==1){
                    a.erase(*it);
                }
                break;
            }
        }
        if(!f){
            s+=*a.rbegin();
            if(i==1){
                a.erase(*a.rbegin());
            }
        }
    }
    return s;
}


/*
int main()
{
   // ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    //freopen(".in","r",stdin);freopen("timeline.out","w",stdout);
    int t=1;
    //cin>>t;
    while(t--) solve();
    return 0;
}
*/

컴파일 시 표준 에러 (stderr) 메시지

combo.cpp: In function 'std::string guess_sequence(int)':
combo.cpp:59:19: error: no match for 'operator==' (operand types are 'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} and 'std::set<char>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<char> >'})
   59 |             if(it == a.rbegin()) break;
      |                ~~ ^~ ~~~~~~~~~~
      |                |             |
      |                |             std::set<char>::reverse_iterator {aka std::reverse_iterator<std::_Rb_tree_const_iterator<char> >}
      |                std::set<char>::iterator {aka std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator}
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from combo.cpp:16:
/usr/include/c++/10/bits/regex.h:1035:5: note: candidate: 'template<class _BiIter> bool std::__cxx11::operator==(const std::__cxx11::sub_match<_BiIter>&, const std::__cxx11::sub_match<_BiIter>&)'
 1035 |     operator==(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1035:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from combo.cpp:16:
/usr/include/c++/10/bits/regex.h:1131:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator==(std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&, const std::__cxx11::sub_match<_BiIter>&)'
 1131 |     operator==(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1131:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from combo.cpp:16:
/usr/include/c++/10/bits/regex.h:1206:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator==(const std::__cxx11::sub_match<_BiIter>&, std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&)'
 1206 |     operator==(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1206:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from combo.cpp:16:
/usr/include/c++/10/bits/regex.h:1298:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator==(const typename std::iterator_traits<_Iter>::value_type*, const std::__cxx11::sub_match<_BiIter>&)'
 1298 |     operator==(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1298:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<char> >'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from combo.cpp:16:
/usr/include/c++/10/bits/regex.h:1373:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator==(const std::__cxx11::sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)'
 1373 |     operator==(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1373:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from combo.cpp:16:
/usr/include/c++/10/bits/regex.h:1466:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator==(const typename std::iterator_traits<_Iter>::value_type&, const std::__cxx11::sub_match<_BiIter>&)'
 1466 |     operator==(typename iterator_traits<_Bi_iter>::value_type const& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1466:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<char> >'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from combo.cpp:16:
/usr/include/c++/10/bits/regex.h:1545:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator==(const std::__cxx11::sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type&)'
 1545 |     operator==(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:1545:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from combo.cpp:16:
/usr/include/c++/10/bits/regex.h:2101:5: note: candidate: 'template<class _Bi_iter, class _Alloc> bool std::__cxx11::operator==(const std::__cxx11::match_results<_BiIter, _Alloc>&, const std::__cxx11::match_results<_BiIter, _Alloc>&)'
 2101 |     operator==(const match_results<_Bi_iter, _Alloc>& __m1,
      |     ^~~~~~~~
/usr/include/c++/10/bits/regex.h:2101:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::__cxx11::match_results<_BiIter, _Alloc>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/iosfwd:40,
                 from /usr/include/c++/10/ios:38,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from combo.cpp:16:
/usr/include/c++/10/bits/postypes.h:222:5: note: candidate: 'template<class _StateT> bool std::operator==(const std::fpos<_StateT>&, const std::fpos<_StateT>&)'
  222 |     operator==(const fpos<_StateT>& __lhs, const fpos<_StateT>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/10/bits/postypes.h:222:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::fpos<_StateT>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:64,
                 from /usr/include/c++/10/bits/char_traits.h:39,
                 from /usr/include/c++/10/ios:40,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from combo.cpp:16:
/usr/include/c++/10/bits/stl_pair.h:466:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator==(const std::pair<_T1, _T2>&, const std::pair<_T1, _T2>&)'
  466 |     operator==(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/10/bits/stl_pair.h:466:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::pair<_T1, _T2>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/char_traits.h:39,
                 from /usr/include/c++/10/ios:40,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from combo.cpp:16:
/usr/include/c++/10/bits/stl_iterator.h:360:5: note: candidate: 'template<class _Iterator> bool std::operator==(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_Iterator>&)'
  360 |     operator==(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/10/bits/stl_iterator.h:360:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::reverse_iterator<_Iterator>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/char_traits.h:39,
                 from /usr/include/c++/10/ios:40,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from combo.cpp:16:
/usr/include/c++/10/bits/stl_iterator.h:398:5: note: candidate: 'template<class _IteratorL, class _IteratorR> bool std::operator==(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_IteratorR>&)'
  398 |     operator==(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/10/bits/stl_iterator.h:398:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::reverse_iterator<_Iterator>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/char_traits.h:39,
                 from /usr/include/c++/10/ios:40,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from combo.cpp:16:
/usr/include/c++/10/bits/stl_iterator.h:1427:5: note: candidate: 'template<class _IteratorL, class _IteratorR> bool std::operator==(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorR>&)'
 1427 |     operator==(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/10/bits/stl_iterator.h:1427:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::move_iterator<_IteratorL>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/char_traits.h:39,
                 from /usr/include/c++/10/ios:40,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from combo.cpp:16:
/usr/include/c++/10/bits/stl_iterator.h:1495:5: note: candidate: 'template<class _Iterator> bool std::operator==(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorL>&)'
 1495 |     operator==(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/10/bits/stl_iterator.h:1495:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::move_iterator<_IteratorL>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/string:41,
                 from /usr/include/c++/10/bits/locale_classes.h:40,
                 from /usr/include/c++/10/bits/ios_base.h:41,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from combo.cpp:16:
/usr/include/c++/10/bits/allocator.h:206:5: note: candidate: 'template<class _T1, class _T2> bool std::operator==(const std::allocator<_CharT>&, const std::allocator<_T2>&)'
  206 |     operator==(const allocator<_T1>&, const allocator<_T2>&)
      |     ^~~~~~~~
/usr/include/c++/10/bits/allocator.h:206:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::allocator<_CharT>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/string:55,
                 from /usr/include/c++/10/bits/locale_classes.h:40,
                 from /usr/include/c++/10/bits/ios_base.h:41,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from combo.cpp:16:
/usr/include/c++/10/bits/basic_string.h:6153:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> bool std::operator==(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)'
 6153 |     operator==(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/basic_string.h:6153:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>'
   59 |             if(it == a.rbegin()) break;
      |                               ^
In file included from /usr/include/c++/10/string:55,
                 from /usr/include/c++/10/bits/locale_classes.h:40,
                 from /usr/include/c++/10/bits/ios_base.h:41,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/istream:38,
                 from /usr/include/c++/10/sstream:38,
                 from /usr/include/c++/10/complex:45,
                 from /usr/include/c++/10/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:54,
                 from combo.cpp:16:
/usr/include/c++/10/bits/basic_string.h:6161:5: note: candidate: 'template<class _CharT> typename __gnu_cxx::__enable_if<std::__is_char<_Tp>::__value, bool>::__type std::operator==(const std::__cxx11::basic_string<_CharT>&, const std::__cxx11::basic_string<_CharT>&)'
 6161 |     operator==(const basic_string<_CharT>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/10/bits/basic_string.h:6161:5: note:   template argument deduction/substitution failed:
combo.cpp:59:31: note:   'std::set<char>::iterator' {aka 'std::_Rb_tree<char, char, std::_Identity<char>, std::less<char>, std::allocator<char> >::const_iterator'} is not derived from 'const std::__cxx11::basic_string