Language: C++

#INCLUDE <BITS/STDC++.H>
typedef long long ll;
const int INF = 1e9;
const int MOD = 1e9+7;
const ll LINF = 1e18;
using namespace std;
 
#define dump(x)  cout << #x << " = " << (x) << endl;
#define YES(n) cout << ((n) ? "YES" : "NO"  ) << endl
#define Yes(n) cout << ((n) ? "Yes" : "No"  ) << endl
#define POSSIBLE(n) cout << ((n) ? "POSSIBLE" : "IMPOSSIBLE"  ) << endl
#define Possible(n) cout << ((n) ? "Possible" : "Impossible"  ) << endl
#define possible(n) cout << ((n) ? "possible" : "impossible"  ) << endl
 
#define SANKOU(n,a,b) cout << ((n) ? (#a) : (#b) ) << endl
 
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) for(int i=0;i<(n);++i)
#define REPR(i,n) for(int i=n;i>=0;i--)
 
#define FOREACH(x,a) for(auto& (x) : (a) )
 
#define WFA(d,v) REP(k,v)REP(i,v)REP(j,v)d[i][j]=min(d[i][j],d[i][k]+d[k][j])
 
#define SCOUT(x) cout<<(x)<<" "
#define ENDL cout<<endl
 
#define VECCIN(x) for(auto&youso_: (x) )cin>>youso_
#define VECIN2(x,y) REP(i,x.size())cin>>x[i]>>y[i]
#define VECCOUT(x) for(auto tt=x.begin();tt!=x.end();tt++){if(tt!=x.begin())cout<<" ";cout<<(*tt);}cout<<endl
 
#define ALL(obj) (obj).begin(),(obj).end()
 
#define EXIST(n,x) (find(ALL(n),x)!=n.end())
#define UNIQUE(obj) sort(ALL( obj )); obj.erase(unique(ALL(obj)),obj.end())
#define COUT(x) cout<<(x)<<endl
void CINT(){}
template <class Head,class... Tail>
void CINT(Head&& head,Tail&&... tail){
    cin>>head;
    CINT(move(tail)...);
}
#define CIN(...) int __VA_ARGS__;CINT(__VA_ARGS__)
#define LCIN(...) ll __VA_ARGS__;CINT(__VA_ARGS__)
#define SCIN(...) string __VA_ARGS__;CINT(__VA_ARGS__)
 
template <class T = ll>
T IN(){T x;cin>>x;return (x);}
 
template <class Head>
void VT(Head head){}
template <class Head,class Seco,class... Tail>
void VT(Head&& head,Seco&& seco,Tail&&... tail){
    seco.resize(head);
    VT(head,move(tail)...);
}
void VT2(){}
template <class Head,class... Tail>
void VT2(Head&& head,Tail&&... tail){
  VECCIN(head);
  VT2(move(tail)...);
}
 
template <class Head>
void VT3(Head&& head){}
template <class Head,class Seco,class... Tail>
void VT3(Head&& head,Seco&& seco,Tail&&... tail){
  seco[head]=IN();
  VT3(head,move(tail)...);
}
 
#define VC1(n,...) V __VA_ARGS__;VT(n,__VA_ARGS__);VT2(__VA_ARGS__); //aaabbbccc
#define VC2(n,...) V __VA_ARGS__;VT(n,__VA_ARGS__);REP(i,n)VT3(i,__VA_ARGS__); //abcabcabc
 
// #include <boost/multiprecision/cpp_int.hpp>
// using namespace boost::multiprecision; // cpp_int
 
#define P pair<int,int>
#define V vector<int>
#define M map<int,int>
#define S set<int>
#define PQ priority_queue<int>
#define PQG priority_queue<int,V,greater<int>>
 
#define str string
 
#define pb(a) push_back(a)
#define mp make_pair

int main(){
  LCIN(n,m);
  if(n>m)swap(n,m);
  if(n==1)
    {COUT(m-2);return 0;}
  if(n==2||m==2){COUT(0);return 0;}
  ll num = 1LL*(n-2)*(m-2);
  COUT(num);


  return 0;
}


Compiler output:
a.cc:1:2: error: invalid preprocessing directive #INCLUDE
    1 | #INCLUDE <BITS/STDC++.H>
      |  ^~~~~~~
a.cc: In function 'void CINT(Head&&, Tail&& ...)':
a.cc:40:5: error: 'cin' was not declared in this scope
   40 |     cin>>head;
      |     ^~~
a.cc:1:1: note: 'std::cin' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
  +++ |+#include <iostream>
    1 | #INCLUDE <BITS/STDC++.H>
a.cc: In function 'T IN()':
a.cc:48:12: error: 'cin' was not declared in this scope
   48 | T IN(){T x;cin>>x;return (x);}
      |            ^~~
a.cc:48:12: note: 'std::cin' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
a.cc: In function 'void VT2(Head&&, Tail&& ...)':
a.cc:28:41: error: 'cin' was not declared in this scope
   28 | #define VECCIN(x) for(auto&youso_: (x) )cin>>youso_
      |                                         ^~~
a.cc:60:3: note: in expansion of macro 'VECCIN'
   60 |   VECCIN(head);
      |   ^~~~~~
a.cc:28:41: note: 'std::cin' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
   28 | #define VECCIN(x) for(auto&youso_: (x) )cin>>youso_
      |                                         ^~~
a.cc:60:3: note: in expansion of macro 'VECCIN'
   60 |   VECCIN(head);
      |   ^~~~~~
a.cc: In function 'int main()':
a.cc:92:10: error: 'swap' was not declared in this scope
   92 |   if(n>m)swap(n,m);
      |          ^~~~
a.cc:36:17: error: 'cout' was not declared in this scope
   36 | #define COUT(x) cout<<(x)<<endl
      |                 ^~~~
a.cc:94:6: note: in expansion of macro 'COUT'
   94 |     {COUT(m-2);return 0;}
      |      ^~~~
a.cc:36:17: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
   36 | #define COUT(x) cout<<(x)<<endl
      |                 ^~~~
a.cc:94:6: note: in expansion of macro 'COUT'
   94 |     {COUT(m-2);return 0;}
      |      ^~~~
a.cc:36:28: error: 'endl' was not declared in this scope
   36 | #define COUT(x) cout<<(x)<<endl
      |                            ^~~~
a.cc:94:6: note: in expansion of macro 'COUT'
   94 |     {COUT(m-2);return 0;}
      |      ^~~~
a.cc:1:1: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
  +++ |+#include <ostream>
    1 | #INCLUDE <BITS/STDC++.H>
a.cc:36:17: error: 'cout' was not declared in this scope
   36 | #define COUT(x) cout<<(x)<<endl
      |                 ^~~~
a.cc:95:18: note: in expansion of macro 'COUT'
   95 |   if(n==2||m==2){COUT(0);return 0;}
      |                  ^~~~
a.cc:36:17: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
   36 | #define COUT(x) cout<<(x)<<endl
      |                 ^~~~
a.cc:95:18: note: in expansion of macro 'COUT'
   95 |   if(n==2||m==2){COUT(0);return 0;}
      |                  ^~~~
a.cc:36:28: error: 'endl' was not declared in this scope
   36 | #define COUT(x) cout<<(x)<<endl
      |                            ^~~~
a.cc:95:18: note: in expansion of macro 'COUT'
   95 |   if(n==2||m==2){COUT(0);return 0;}
      |                  ^~~~
a.cc:36:28: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
   36 | #define COUT(x) cout<<(x)<<endl
      |                            ^~~~
a.cc:95:18: note: in expansion of macro 'COUT'
   95 |   if(n==2||m==2){COUT(0);return 0;}
      |                  ^~~~
a.cc:36:17: error: 'cout' was not declared in this scope
   36 | #define COUT(x) cout<<(x)<<endl
      |                 ^~~~
a.cc:97:3: note: in expansion of macro 'COUT'
   97 |   COUT(num);
      |   ^~~~
a.cc:36:17: note: 'std::cout' is defined in header '<iostream>'; this is probably fixable by adding '#include <iostream>'
   36 | #define COUT(x) cout<<(x)<<endl
      |                 ^~~~
a.cc:97:3: note: in expansion of macro 'COUT'
   97 |   COUT(num);
      |   ^~~~
a.cc:36:28: error: 'endl' was not declared in this scope
   36 | #define COUT(x) cout<<(x)<<endl
      |                            ^~~~
a.cc:97:3: note: in expansion of macro 'COUT'
   97 |   COUT(num);
      |   ^~~~
a.cc:36:28: note: 'std::endl' is defined in header '<ostream>'; this is probably fixable by adding '#include <ostream>'
   36 | #define COUT(x) cout<<(x)<<endl
      |                            ^~~~
a.cc:97:3: note: in expansion of macro 'COUT'
   97 |   COUT(num);
      |   ^~~~
a.cc: In instantiation of 'void CINT(Head&&, Tail&& ...) [with Head = long long int&; Tail = {long long int&}]':
a.cc:91:3:   required from here
   44 | #define LCIN(...) ll __VA_ARGS__;CINT(__VA_ARGS__)
      |                                  ~~~~^~~~~~~~~~~~~
a.cc:41:14: error: 'move' was not declared in this scope
   41 |     CINT(move(tail)...);
      |          ~~~~^~~~~~
a.cc:1:1: note: 'std::move' is defined in header '<utility>'; this is probably fixable by adding '#include <utility>'
  +++ |+#include <utility>
    1 | #INCLUDE <BITS/STDC++.H>