Language: C++

#include <iostream>
#include <cstdlib>
#include <vector>
#include <algorithm>
#include <math.h>
using namespace std;

int main()
{
    long n, m;
    long answer;
    cin >> n >> m;
    if (n == 1 && m == 1){
        answer = 1;
    }
    else if (n == 1 && m > 2){
        answer = max(0, m-2);
    }
    else if (m == 1 && n > 2){
        answer = max(0, n-2);
    }
    else if ((n == 2 && m > 2) || (m == 2 && n > 2)){
        answer = 0;
    }
    else { // n >= 3 && m >= 3
        answer = (n-2)*(m-2);
    }
    cout << answer << endl;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:17:21: error: no matching function for call to 'max(int, long int)'
   17 |         answer = max(0, m-2);
      |                  ~~~^~~~~~~~
In file included from /usr/include/c++/14/string:51,
                 from /usr/include/c++/14/bits/locale_classes.h:40,
                 from /usr/include/c++/14/bits/ios_base.h:41,
                 from /usr/include/c++/14/ios:44,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 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:17:21: note:   deduced conflicting types for parameter 'const _Tp' ('int' and 'long int')
   17 |         answer = max(0, m-2);
      |                  ~~~^~~~~~~~
/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,
                 from a.cc:4:
/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:17:21: note:   mismatched types 'std::initializer_list<_Tp>' and 'int'
   17 |         answer = max(0, m-2);
      |                  ~~~^~~~~~~~
a.cc:20:21: error: no matching function for call to 'max(int, long int)'
   20 |         answer = max(0, n-2);
      |                  ~~~^~~~~~~~
/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:20:21: note:   deduced conflicting types for parameter 'const _Tp' ('int' and 'long int')
   20 |         answer = max(0, n-2);
      |                  ~~~^~~~~~~~
/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:20:21: note:   mismatched types 'std::initializer_list<_Tp>' and 'int'
   20 |         answer = max(0, n-2);
      |                  ~~~^~~~~~~~