Language: C++

#include <bits/stdc++.h>
using namespace std;

const int maxn = 300005;
set<pair<int, int>> s;
int cntx[maxn], cnty[maxn];
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int h, w, m, x, y, ma = 0, saved;
    unsigned int res = 0;
    cin >> h >> w >> m;
    for (int i = 1; i <= m; i++) {
        cin >> x >> y;
        cntx[x]++;
        cnty[y]++;
        s.insert({x, y});
    }
    for (int i = 1; i <= w; i++)
        if (cnty[i]>ma) {
            ma = cnty[i];
            saved = i;
        }
    for (int i = 1; i <= h; i++) {
        res = max(res, ma+cntx[i]-s.count({i, saved}));
    }
    for (int i = 1; i <= h; i++) {
        if (cntx[i]>ma) {
            ma = cntx[i];
            saved = i;
        }
    }
    for (int i = 1; i <= w; i++) {
        res = max(res, ma+cnty[i]-s.count({saved, i}));
    }
    cout << res;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:25:18: error: no matching function for call to 'max(unsigned int&, std::set<std::pair<int, int> >::size_type)'
   25 |         res = max(res, ma+cntx[i]-s.count({i, saved}));
      |               ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51,
                 from a.cc:1:
/usr/include/c++/14/bits/stl_algobase.h:257:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::max(const _Tp&, const _Tp&)'
  257 |     max(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note:   template argument deduction/substitution failed:
a.cc:25:18: note:   deduced conflicting types for parameter 'const _Tp' ('unsigned int' and 'std::set<std::pair<int, int> >::size_type' {aka 'long unsigned int'})
   25 |         res = max(res, ma+cntx[i]-s.count({i, saved}));
      |               ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::max(const _Tp&, const _Tp&, _Compare)'
  303 |     max(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note:   candidate expects 3 arguments, 2 provided
In file included from /usr/include/c++/14/algorithm:61:
/usr/include/c++/14/bits/stl_algo.h:5706:5: note: candidate: 'template<class _Tp> constexpr _Tp std::max(initializer_list<_Tp>)'
 5706 |     max(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5706:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5716:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::max(initializer_list<_Tp>, _Compare)'
 5716 |     max(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5716:5: note:   template argument deduction/substitution failed:
a.cc:25:18: note:   mismatched types 'std::initializer_list<_Tp>' and 'unsigned int'
   25 |         res = max(res, ma+cntx[i]-s.count({i, saved}));
      |               ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
a.cc:34:18: error: no matching function for call to 'max(unsigned int&, std::set<std::pair<int, int> >::size_type)'
   34 |         res = max(res, ma+cnty[i]-s.count({saved, i}));
      |               ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note: candidate: 'template<class _Tp> constexpr const _Tp& std::max(const _Tp&, const _Tp&)'
  257 |     max(const _Tp& __a, const _Tp& __b)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:257:5: note:   template argument deduction/substitution failed:
a.cc:34:18: note:   deduced conflicting types for parameter 'const _Tp' ('unsigned int' and 'std::set<std::pair<int, int> >::size_type' {aka 'long unsigned int'})
   34 |         res = max(res, ma+cnty[i]-s.count({saved, i}));
      |               ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note: candidate: 'template<class _Tp, class _Compare> constexpr const _Tp& std::max(const _Tp&, const _Tp&, _Compare)'
  303 |     max(const _Tp& __a, const _Tp& __b, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algobase.h:303:5: note:   candidate expects 3 arguments, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5706:5: note: candidate: 'template<class _Tp> constexpr _Tp std::max(initializer_list<_Tp>)'
 5706 |     max(initializer_list<_Tp> __l)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5706:5: note:   candidate expects 1 argument, 2 provided
/usr/include/c++/14/bits/stl_algo.h:5716:5: note: candidate: 'template<class _Tp, class _Compare> constexpr _Tp std::max(initializer_list<_Tp>, _Compare)'
 5716 |     max(initializer_list<_Tp> __l, _Compare __comp)
      |     ^~~
/usr/include/c++/14/bits/stl_algo.h:5716:5: note:   template argument deduction/substitution failed:
a.cc:34:18: note:   mismatched types 'std::initializer_list<_Tp>' and 'unsigned int'
   34 |         res = max(res, ma+cnty[i]-s.count({saved, i}));
      |               ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~