Language: C++

/* 

 */
/* ID: thanhvq1
LANG: C++14
PROB: namenum
*/

#pragma GCC optimize ("O2")
#include<bits/stdc++.h>
#include<unistd.h>
using namespace std;

// defines
#define int long long
typedef long long ll;
#define double long double
#define vec vector
#define vi vector<int>
#define vvi vector<vector<int>>
#define FZ(n) memset((n),0,sizeof())
#define FMO(n) memset((n),-1,sizeof(n))
#define unset unordered_set
#define ii pair<int, int>
#define vii vector<ii>
#define F first
#define S second
#define mp make_pair
#define PB push_back
#define ALL(x) begin(x),end(x)
#define SZ(x) ((int)(x).size())
#define FOR(i, a, b) for(int i = (a); i < (b); i++)
#define FORE(i, a, b) for(int i = (a); i <= (b); i++)
#define FORD(i, a, b) for(int i = (a); i >= (b); i--)
#define bitcount(n) __builtin_popcountll(n)
#define reset(x, y) memset(x, y, sizeof(x))
#define uni(x) (x).erase(unique(all(x)), (x).end());
#define debug(x) cout << #x << " = " << (x) << endl
#define debug2(x, y) cout<<#x<<" = "<<(x)<<", "<<#y<<" = "<<(y)<< endl
#define debug3(x, y, z) cout<<#x<<" = "<<(x)<<", "<<#y<<" = "<<(y)<<", "<<#z<<" = "<<(z)<<endl
#define chkmin(a, b) a = min(a, b)
#define chkmax(a, b) a = max(a, b)
#define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
#define min3(a, b, c) min(a, b) < min(b, c) ? min(a, b) : min(b, c)

//permanent constants
const long long INF64 = 1e18; const int INF32 = 1e9; const int BIG = (int)(1e9 + 239);
const int MOD = 998244353; //1e9 + 7;  const ll MOD2 = (ll)MOD * (ll)MOD;
const double PI = 2.0*acos(0.0); //acos(-1.0L);
const double EPS = static_cast<double>(1e-10);
const int day[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
const int dx[4] = {0, 1, 0, -1}; const int dy[4] = {1, 0, -1, 0};
//const ll INF = (ll)(1e18 + 239);

//random
mt19937 rnd(239); //(chrono::high_resolution_clock::now().time_since_epoch().count());

void FILEIO() {  freopen("in.txt", "r", stdin);  freopen("out.txt", "w", stdout); }
//void FILEIO()   {freopen("in.txt", "w", stdout);}
//void FILEIO() {  freopen("namenum.in", "r", stdin);  freopen("namenum.out", "w", stdout); }
void input() {   }

int cost[10][10][10][10]; // cost[s][k][x][y] = min cost to get k from s, with counter x - y 


void solve() {
	int a, b; cin >> a >> b;
	cout << max3(a+b, a-b, a*b) << endl;
}

signed main() {
  ios_base::sync_with_stdio(false); cin.tie();
//  FILEIO();
//auto beginProgram = chrono::steady_clock::now();

//	int const T=10, N = 100000;
//	cout << T << endl;
//	FOR(i, 0, T) {
//		cout << N << endl;
//		FOR(i, 0, N) cout << "0 " ;
//		cout << endl;
//	}

//  int test = 0;
//  int t; cin >> t;
//  while(t--)
  {
//	  cout << "Case " << ++test << ": ";
	  solve();
  }

//  auto endProgram = chrono::steady_clock::now();
//  cout << chrono::duration_cast<chrono::milliseconds>(endProgram - beginProgram).count() << " ms" << endl;

  return 0;
}



Compiler output:
a.cc: In function 'void solve()':
a.cc:43:33: error: no match for 'operator>' (operand types are 'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} and 'const long long int')
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                 ^ ~~~~~~~~~
      |                                      |
      |                                      const long long int
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
a.cc:43:33: note: candidate: 'operator>(int, long long int)' (built-in)
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                 ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
a.cc:43:33: note:   no known conversion for argument 1 from 'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} to 'int'
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                 ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
In file included from /usr/include/c++/14/regex:68,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:181,
                 from a.cc:10:
/usr/include/c++/14/bits/regex.h:1176:5: note: candidate: 'template<class _BiIter> bool std::__cxx11::operator>(const sub_match<_BiIter>&, const sub_match<_BiIter>&)'
 1176 |     operator>(const sub_match<_BiIter>& __lhs, const sub_match<_BiIter>& __rhs)
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1176:5: note:   template argument deduction/substitution failed:
a.cc:43:43: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                           ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
/usr/include/c++/14/bits/regex.h:1236:5: 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>&)'
 1236 |     operator>(const __sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1236:5: note:   template argument deduction/substitution failed:
a.cc:43:43: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'std::__cxx11::__sub_match_string<_Bi_iter, _Ch_traits, _Ch_alloc>'
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                           ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
/usr/include/c++/14/bits/regex.h:1329:5: 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>&)'
 1329 |     operator>(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1329:5: note:   template argument deduction/substitution failed:
a.cc:43:43: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                           ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
/usr/include/c++/14/bits/regex.h:1403:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>(const typename std::iterator_traits<_Iter>::value_type*, const sub_match<_BiIter>&)'
 1403 |     operator>(typename iterator_traits<_Bi_iter>::value_type const* __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1403:5: note:   template argument deduction/substitution failed:
a.cc:43:43: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'const long long int'
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                           ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
/usr/include/c++/14/bits/regex.h:1497:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type*)'
 1497 |     operator>(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1497:5: note:   template argument deduction/substitution failed:
a.cc:43:43: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                           ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
/usr/include/c++/14/bits/regex.h:1573:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>(const typename std::iterator_traits<_Iter>::value_type&, const sub_match<_BiIter>&)'
 1573 |     operator>(typename iterator_traits<_Bi_iter>::value_type const& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1573:5: note:   template argument deduction/substitution failed:
a.cc:43:43: note:   mismatched types 'const std::__cxx11::sub_match<_BiIter>' and 'const long long int'
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                           ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
/usr/include/c++/14/bits/regex.h:1673:5: note: candidate: 'template<class _Bi_iter> bool std::__cxx11::operator>(const sub_match<_BiIter>&, const typename std::iterator_traits<_Iter>::value_type&)'
 1673 |     operator>(const sub_match<_Bi_iter>& __lhs,
      |     ^~~~~~~~
/usr/include/c++/14/bits/regex.h:1673:5: note:   template argument deduction/substitution failed:
a.cc:43:43: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::__cxx11::sub_match<_BiIter>'
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                           ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:64,
                 from /usr/include/c++/14/algorithm:60,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:51:
/usr/include/c++/14/bits/stl_pair.h:1058:5: note: candidate: 'template<class _T1, class _T2> constexpr bool std::operator>(const pair<_T1, _T2>&, const pair<_T1, _T2>&)'
 1058 |     operator>(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_pair.h:1058:5: note:   template argument deduction/substitution failed:
a.cc:43:43: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::pair<_T1, _T2>'
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                           ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
In file included from /usr/include/c++/14/bits/stl_algobase.h:67:
/usr/include/c++/14/bits/stl_iterator.h:462:5: note: candidate: 'template<class _Iterator> constexpr bool std::operator>(const reverse_iterator<_Iterator>&, const reverse_iterator<_Iterator>&)'
  462 |     operator>(const reverse_iterator<_Iterator>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:462:5: note:   template argument deduction/substitution failed:
a.cc:43:43: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::reverse_iterator<_Iterator>'
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                           ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
/usr/include/c++/14/bits/stl_iterator.h:507:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator>(const reverse_iterator<_Iterator>&, const reverse_iterator<_IteratorR>&)'
  507 |     operator>(const reverse_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:507:5: note:   template argument deduction/substitution failed:
a.cc:43:43: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::reverse_iterator<_Iterator>'
   43 | #define max3(a, b, c) max(a, b) > max(b, c) ? max(a, b) : max(b, c)
      |                                           ^
a.cc:68:17: note: in expansion of macro 'max3'
   68 |         cout << max3(a+b, a-b, a*b) << endl;
      |                 ^~~~
/usr/include/c++/14/bits/stl_iterator.h:1714:5: note: candidate: 'template<class _IteratorL, class _IteratorR> constexpr bool std::operator>(const move_iterator<_IteratorL>&, const move_iterator<_IteratorR>&)'
 1714 |     operator>(const move_iterator<_IteratorL>& __x,
      |     ^~~~~~~~
/usr/include/c++/14/bits/stl_iterator.h:1714:5: note:   template argument deduction/substitution failed:
a.cc:43:43: note:   'std::basic_ostream<char>::__ostream_type' {aka 'std::basic_ostream<char>'} is not derived from 'const std::move_iterator<_IteratorL>'
   43 | #define max3(a,