Language: C++

#include<bits/stdc++.h>

using namespace std;

#define debug(n) cerr << #n << ':' << n << endl;
#define dline    cerr << __LINE__ << endl;

using ll = long long;
template<class T, class U> using P = pair<T,U>;
template<class T> using Heap = priority_queue<T>;
template<class T> using heaP = priority_queue<T,vector<T>,greater<T>>;
template<class T,class U> using umap = unordered_map<T,U>;
template<class T> using uset = unordered_set<T>;

template<class T>
bool ChangeMax(T&a,const T&b){
  if(a >= b) return false;
  a = b;    return true;
}

template<class T>
bool ChangeMin(T&a,const T&b){
  if(a <= b) return false;
  a = b;    return true;  
}

template<class T, size_t N, class U>
void Fill(T (&a)[N], const U&v){
    fill((U*)a,(U*)(a+N),v);
}

template<class T>
istream& operator >> (istream&is, vector<T>&v){
  for(auto&e:v)is >> e;
  return is;
}

int main(){
  int h,w,m; cin >> h >> w >> m;
  static vector<P<int,int>> b(m);
  int cntr[300001] = {};
  int cntc[300001] = {};
  int maxr=0,maxc=0;
  for(int i = 0; i < m; ++i){
    cin >> b[i].first >> b[i].second;
    ChangeMax(maxr,++cntr[b[i].first]);
    ChangeMax(maxc,++cntc[b[i].second]);    
  }
  vector<int> r,c;
  for(int i = 1; i <= h; ++i)if(maxr == cntr[i])r.push_back(i);
  for(int i = 1; i <= w; ++i)if(maxc == cntc[i])c.push_back(i);
  int cntd = 0;
  for(auto e:b)
    cntd += binary_search(r.begin(),r.end(),e)&&binary_search(c.begin(),c.end(),e);
  cout << maxr + maxc - (dcnt == (int)r.size()*(int)c.size()) << endl;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:55:26: error: 'dcnt' was not declared in this scope
   55 |   cout << maxr + maxc - (dcnt == (int)r.size()*(int)c.size()) << endl;
      |                          ^~~~
In file included from /usr/include/c++/14/algorithm:61,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_algo.h: In instantiation of 'bool std::binary_search(_FIter, _FIter, const _Tp&) [with _FIter = __gnu_cxx::__normal_iterator<int*, vector<int> >; _Tp = pair<int, int>]':
a.cc:54:26:   required from here
   54 |     cntd += binary_search(r.begin(),r.end(),e)&&binary_search(c.begin(),c.end(),e);
      |             ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algo.h:2207:39: error: no match for 'operator<' (operand types are 'const std::pair<int, int>' and 'int')
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/algorithm:60:
/usr/include/c++/14/bits/stl_pair.h:1045:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator<(const pair<_T1, _T2>&, const pair<_T1, _T2>&)'
 1045 |     operator<(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_pair.h:1045:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   mismatched types 'const std::pair<_T1, _T2>' and 'int'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:67:
/usr/include/c++/14/bits/stl_iterator.h:448:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)'
  448 |     operator<(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:448:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   'const std::pair<int, int>' is not derived from 'const std::reverse_iterator<_Iterator>'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:493:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)'
  493 |     operator<(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:493:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   'const std::pair<int, int>' is not derived from 'const std::reverse_iterator<_Iterator>'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1694:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator<(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)'
 1694 |     operator<(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1694:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   'const std::pair<int, int>' is not derived from 'const std::move_iterator<_IteratorL>'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1760:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator<(const move_iterator<_IteratorL>&, const move_iterator<_IteratorL>&)'
 1760 |     operator<(const move_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1760:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   'const std::pair<int, int>' is not derived from 'const std::move_iterator<_IteratorL>'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
In file included from /usr/include/c++/14/regex:68,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:181:
/usr/include/c++/14/bits/regex.h:1143:5: note: candidate: 'template<class _BiIter> bool std::__cxx11::operator<(const sub_match<_BiIter>&, const sub_match<_BiIter>&)'
 1143 |     operator<(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1143:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   'const std::pair<int, int>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
/usr/include/c++/14/bits/regex.h:1224:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator<(__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&, const sub_match<_BiIter>&)'
 1224 |     operator<(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1224:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   'const std::pair<int, int>' is not derived from 'std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
/usr/include/c++/14/bits/regex.h:1317:5: note: candidate: 'template<class _Bi_iter, class _Ch_traits, class _Ch_alloc> bool std::__cxx11::operator<(const sub_match<_BiIter>&, __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>&)'
 1317 |     operator<(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1317:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   'const std::pair<int, int>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
/usr/include/c++/14/bits/regex.h:1391:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<(const typename std::iterator_traits<_Iter>::value_type*, const sub_match<_BiIter>&)'
 1391 |     operator<(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1391:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
/usr/include/c++/14/bits/regex.h:1485:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)'
 1485 |     operator<(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1485:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   'const std::pair<int, int>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
/usr/include/c++/14/bits/regex.h:1560:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<(const typename std::iterator_traits<_Iter>::value_type&, const sub_match<_BiIter>&)'
 1560 |     operator<(typename iterator_traits<_Bi_iter>::value_type const& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1560:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'int'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
/usr/include/c++/14/bits/regex.h:1660:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator<(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type&)'
 1660 |     operator<(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1660:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   'const std::pair<int, int>' is not derived from 'const std::__cxx11::sub_match<_BiIter>'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
In file included from /usr/include/c++/14/forward_list:40,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:175:
/usr/include/c++/14/bits/forward_list.h:1498:5: note: candidate: 'template<class _Tp, class _Alloc> bool std::operator<(const forward_list<_Tp, _Alloc>&, const forward_list<_Tp, _Alloc>&)'
 1498 |     operator<(const forward_list<_Tp, _Alloc>& __lx,
      |     ^~~~~~~~
/usr/include/c++/14/bits/forward_list.h:1498:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/bits/stl_algo.h:2207:39: note:   'const std::pair<int, int>' is not derived from 'const std::forward_list<_Tp, _Alloc>'
 2207 |       return __i != __last && !(__val < *__i);
      |                                ~~~~~~~^~~~~~~
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:166:
/usr/include/c++/14/valarray:1210:1: note: candidate: 'template<class _Tp> std::_Expr<std::__detail::_BinClos<std::__less, std::_Constant, std::_ValArray, _Tp, _Tp>, typename std::__fun<std::__less, _Tp>::result_type> std::operator<(const typename valarray<_Tp>::value_type&, const valarray<_Tp>&)'
 1210 | _DEFINE_BINARY_OPERATOR(<, __less)
      | ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/valarray:1210:1: note:   template argument deduction/