Submission #1121811

#	Time	Username	Problem	Language	Result	Execution time	Memory
1121811		epicci23	Horses (IOI15_horses)	C++17	Compilation error	0 ms	0 KiB

horses

#include "bits/stdc++.h"
#include "horses.h"
using namespace std;
#define ll long long
#define all(x) x.begin(),x.end()
#define sz(x) (ll)x.size()
 
const ll N = 5e5 + 5;
const ll INF = 1e18 + 5;
const ll MOD = 1e9 + 7;
 
inline ll add(ll a,ll b){
  if(a+b>=MOD) return a+b-MOD;
  return a+b;
}
 
inline ll mult(ll a,ll b){
  if(a*b>=MOD) return a*b%MOD;
  return a*b;
}
 
inline ll fast(ll a,ll b,ll res=1){
  for(;b;a=mult(a,a),b>>=1) if(b&1) res=mult(res,a);
  return res;
}
 
inline ll inv(ll a){
  return fast(a,MOD-2);
}
 
struct SegT{
  vector<ll> seg;
  ll n,def;
  SegT(ll _n,ll _def){
  	n=_n,def=_def;
    seg.assign(4*n+5,def);
  }
  void upd(ll rt,ll l,ll r,ll ind,ll u){
  	if(r<ind || l>ind) return;
  	if(l==r){
  	  seg[rt]=u;
  	  return;
  	}
    ll mid=(l+r)/2;
    upd(rt*2,l,mid,ind,u),upd(rt*2+1,mid+1,r,ind,u);
    seg[rt]=max(seg[rt*2],seg[rt*2+1]);
  }
  ll query(ll rt,ll l,ll r,ll gl,ll gr){
    if(r<gl || l>gr) return def;
    if(l>=gl && r<=gr) return seg[rt];
    ll mid=(l+r)/2;
    return max(query(rt*2,l,mid,gl,gr),query(rt*2+1,mid+1,r,gl,gr));
  }
};
 
ll fw[N],n;
set<ll> s;
SegT T(N,-INF);
array<ll,2> ar[N];
 
inline void upd(ll c,ll u){
  for(;c<N;c+=c&-c) fw[c]=mult(fw[c],u);
}
 
inline ll query(ll c,ll res=1){
  for(;c;c-=c&-c) res=mult(res,fw[c]);
  return res;
}
 
inline ll find_ans(){
  vector<ll> v;
  set<ll>::reverse_iterator it = s.rbegin();
  ll ekle = 100;
  while(ekle--){
  	v.push_back(*it);
  	if(it==s.begin()) break;
  	it++;
  }
  reverse(all(v));
  ll m = sz(v);
  vector<ll> g;
  for(ll i = 0; i < m; i++) g.push_back(T.query(1,1,n,v[i],(i+1==m ? n+1 : v[i+1])-1));
  ll best = 0 , as = 1;
  for(ll i = 1 ; i < m ;i++){
  	ll ind = v[i];
  	as *= ar[ind][0];
  	if(as >= (g[best]+g[i]-1)/g[i]){
  	  best = i;
  	  as = 1;
  	}
  }
  return mult(g[best],query(v[best]));
}
 
int init(int nn, int X[], int Y[]){
  n = nn;
  for(ll i = 1; i <= n ; i++) ar[i][0] = X[i-1], ar[i][1] = Y[i-1];
  fill(fw,fw+N,1);
  for(ll i = 1 ; i <= n ; i++) upd(i,ar[i][0]);
  s.insert(1);
  for(ll i=2;i<=n;i++) if(ar[i][0] >= 2) s.insert(i);
  for(ll i=1;i<=n;i++) T.upd(1,1,n,i,ar[i][1]);
 
  return (int)find_ans();
}
 
int updateX(int pos, int val){	
  if(pos >= 2) s.erase(pos);
  upd(pos,inv(ar[pos][0]));
  
  ar[pos][0] = val;
  if(pos >= 2 && val >= 2) s.insert(pos);  
  upd(pos,val);

  return (int)find_ans();
}
 
int updateY(int pos, int val){
  ar[(ll)pos][1] = (ll) val;
  T.upd(1,1,n,(ll)pos,ar[pos][1]);
  return (int)find_ans();
}
 
/*void _(){
  cin >> n; 
  for(ll i = 1; i <= n ; i++) cin >> ar[i][0] >> ar[i][1];
  fill(fw,fw+N,1);
  for(ll i = 1 ; i <= n ; i++) upd(i,ar[i][0]);
  for(ll i=1;i<=n;i++) if(ar[i][0] >= 2) s.insert(i);
  for(ll i=1;i<=n;i++) T.upd(1,1,n,i,ar[i][1]);
 
}
 
int32_t main(){
  ios::sync_with_stdio(0);
  cin.tie(0);
  ll tc=1;//cin >> tc;
  while(tc--) _();
}*/

Compilation message (stderr)

horses.cpp: In function 'long long int find_ans()':
horses.cpp:76:9: error: no match for 'operator==' (operand types are 'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} and 'std::set<long long int>::iterator' {aka 'std::_Rb_tree<long long int, long long int, std::_Identity<long long int>, std::less<long long int>, std::allocator<long long int> >::const_iterator'})
   76 |    if(it==s.begin()) break;
      |       ~~^~~~~~~~~~~
      |       |          |
      |       |          std::set<long long int>::iterator {aka std::_Rb_tree<long long int, long long int, std::_Identity<long long int>, std::less<long long int>, std::allocator<long long int> >::const_iterator}
      |       std::set<long long int>::reverse_iterator {aka std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >}
In file included from /usr/include/c++/10/regex:62,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:110,
                 from horses.cpp:1:
/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:
horses.cpp:76:19: note:   'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   76 |    if(it==s.begin()) 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 horses.cpp:1:
/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:
horses.cpp:76:19: note:   'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} is not derived from 'std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>'
   76 |    if(it==s.begin()) 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 horses.cpp:1:
/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:
horses.cpp:76:19: note:   'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   76 |    if(it==s.begin()) 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 horses.cpp:1:
/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:
horses.cpp:76:19: note:   'std::set<long long int>::iterator' {aka 'std::_Rb_tree<long long int, long long int, std::_Identity<long long int>, std::less<long long int>, std::allocator<long long int> >::const_iterator'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   76 |    if(it==s.begin()) 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 horses.cpp:1:
/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:
horses.cpp:76:19: note:   'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   76 |    if(it==s.begin()) 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 horses.cpp:1:
/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:
horses.cpp:76:19: note:   'std::set<long long int>::iterator' {aka 'std::_Rb_tree<long long int, long long int, std::_Identity<long long int>, std::less<long long int>, std::allocator<long long int> >::const_iterator'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   76 |    if(it==s.begin()) 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 horses.cpp:1:
/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:
horses.cpp:76:19: note:   'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   76 |    if(it==s.begin()) 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 horses.cpp:1:
/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:
horses.cpp:76:19: note:   'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} is not derived from 'const std::__cxx11::match_results<_BiIter, _Alloc>'
   76 |    if(it==s.begin()) break;
      |                   ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:64,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:41,
                 from horses.cpp:1:
/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:
horses.cpp:76:19: note:   'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} is not derived from 'const std::pair<_T1, _T2>'
   76 |    if(it==s.begin()) break;
      |                   ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:41,
                 from horses.cpp:1:
/usr/include/c++/10/bits/stl_iterator.h:360:5: note: candidate: 'template<class _Iterator> constexpr 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:
horses.cpp:76:19: note:   'std::set<long long int>::iterator' {aka 'std::_Rb_tree<long long int, long long int, std::_Identity<long long int>, std::less<long long int>, std::allocator<long long int> >::const_iterator'} is not derived from 'const std::reverse_iterator<_Iterator>'
   76 |    if(it==s.begin()) break;
      |                   ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:41,
                 from horses.cpp:1:
/usr/include/c++/10/bits/stl_iterator.h:398:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr 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:
horses.cpp:76:19: note:   'std::set<long long int>::iterator' {aka 'std::_Rb_tree<long long int, long long int, std::_Identity<long long int>, std::less<long long int>, std::allocator<long long int> >::const_iterator'} is not derived from 'const std::reverse_iterator<_IteratorR>'
   76 |    if(it==s.begin()) break;
      |                   ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:41,
                 from horses.cpp:1:
/usr/include/c++/10/bits/stl_iterator.h:1427:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr 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:
horses.cpp:76:19: note:   'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} is not derived from 'const std::move_iterator<_IteratorL>'
   76 |    if(it==s.begin()) break;
      |                   ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:67,
                 from /usr/include/c++/10/bits/specfun.h:45,
                 from /usr/include/c++/10/cmath:1927,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:41,
                 from horses.cpp:1:
/usr/include/c++/10/bits/stl_iterator.h:1495:5: note: candidate: 'template<class _Iterator> constexpr 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:
horses.cpp:76:19: note:   'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} is not derived from 'const std::move_iterator<_IteratorL>'
   76 |    if(it==s.begin()) 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 horses.cpp:1:
/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:
horses.cpp:76:19: note:   'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} is not derived from 'const std::fpos<_StateT>'
   76 |    if(it==s.begin()) 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 horses.cpp:1:
/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:
horses.cpp:76:19: note:   'std::set<long long int>::reverse_iterator' {aka 'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >'} is not derived from 'const std::allocator<_CharT>'
   76 |    if(it==s.begin()) break;
      |                   ^
In file included from /usr/include/c++/10/bits/basic_string.h:48,
                 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 horses.cpp:1:
/usr/include/c++/10/string_view:490:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator==(std::basic_string_view<_CharT, _Traits>, std::basic_string_view<_CharT, _Traits>)'
  490 |     operator==(basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/10/string_view:490:5: note:   template argument deduction/substitution failed:
horses.cpp:76:19: note:   'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   76 |    if(it==s.begin()) break;
      |                   ^
In file included from /usr/include/c++/10/bits/basic_string.h:48,
                 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 horses.cpp:1:
/usr/include/c++/10/string_view:496:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator==(std::basic_string_view<_CharT, _Traits>, std::__type_identity_t<std::basic_string_view<_CharT, _Traits> >)'
  496 |     operator==(basic_string_view<_CharT, _Traits> __x,
      |     ^~~~~~~~
/usr/include/c++/10/string_view:496:5: note:   template argument deduction/substitution failed:
horses.cpp:76:19: note:   'std::reverse_iterator<std::_Rb_tree_const_iterator<long long int> >' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   76 |    if(it==s.begin()) break;
      |                   ^
In file included from /usr/include/c++/10/bits/basic_string.h:48,
                 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 horses.cpp:1:
/usr/include/c++/10/string_view:519:5: note: candidate: 'template<class _CharT, class _Traits> constexpr bool std::operator==(std::__type_identity_t<std::basic_string_view<_CharT, _Traits> >, std::basic_string_view<_CharT, _Traits>)'
  519 |     operator==(__type_identity_t<basic_string_view<_CharT, _Traits>> __x,
      |     ^~~~~~~~
/usr/include/c++/10/string_view:519:5: note:   template argument deduction/substitution failed:
horses.cpp:76:19: note:   'std::_Rb_tree_const_iterator<long long int>' is not derived from 'std::basic_string_view<_CharT, _Traits>'
   76 |    if(it==s.begin()) break;
      |                   ^
In file included from /usr