Language: C++

#include <bits/stdc++.h>
#define ll long long
#define rep(X,N) for(int X = 0; X < N; X++)
#define PI (acos(-1.0))
#define sorta(V) sort(V.begin(), V.end())

using namespace std;

int main(){

    ll n,m;

    cin >> n >> m;

    if(n != 1 && m != 1){

        cout << max(0, n - 2) * max(0, m - 2) << endl;
    }else if(n == 1 && m == 1){
        cout << 1 << endl;
    }else{
        cout << n * m - 2 << endl;
    }


    return 0;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:17:20: error: no matching function for call to 'max(int, long long int)'
   17 |         cout << max(0, n - 2) * max(0, m - 2) << endl;
      |                 ~~~^~~~~~~~~~
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:17:20: note:   deduced conflicting types for parameter 'const _Tp' ('int' and 'long long int')
   17 |         cout << max(0, n - 2) * max(0, m - 2) << endl;
      |                 ~~~^~~~~~~~~~
/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:17:20: note:   mismatched types 'std::initializer_list<_Tp>' and 'int'
   17 |         cout << max(0, n - 2) * max(0, m - 2) << endl;
      |                 ~~~^~~~~~~~~~
a.cc:17:36: error: no matching function for call to 'max(int, long long int)'
   17 |         cout << max(0, n - 2) * max(0, m - 2) << endl;
      |                                 ~~~^~~~~~~~~~
/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:17:36: note:   deduced conflicting types for parameter 'const _Tp' ('int' and 'long long int')
   17 |         cout << max(0, n - 2) * max(0, m - 2) << endl;
      |                                 ~~~^~~~~~~~~~
/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:17:36: note:   mismatched types 'std::initializer_list<_Tp>' and 'int'
   17 |         cout << max(0, n - 2) * max(0, m - 2) << endl;
      |                                 ~~~^~~~~~~~~~