Language: C++

#include <bits/stdc++.h>
#define int long long // at least int64 > 9*10^18
#define ENDL '\n'
#define rep(i,n) for(int i = 0; i < (n); i++)
#define print(i) std::cout << (i) << '\n'
#define all(v) (v).begin(), (v).end()

using namepsace std;

signed main (){
  int H,W;
  cin>>H>>N;
  vector<string> a(H);
  rep(i,H){
    cin>>a[i];
  }
  vector<bool> row(H, false);
  vector<bool> col(W, false);
  rep(i,H){
    rep(j,W){
      if(a[i][j]=='#'){
        row[i]=true;
        col[j]=true;
      }
    }
  }
  rep(i,H){
    if(row[i]){
      rep(j,W){
        if(col[j]){
          cout<<a[i][j] ;
        }
      }
      cout<<endl;
    }
  }
}

Compiler output:
a.cc:8:7: error: expected nested-name-specifier before 'namepsace'
    8 | using namepsace std;
      |       ^~~~~~~~~
a.cc: In function 'int main()':
a.cc:12:3: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
   12 |   cin>>H>>N;
      |   ^~~
      |   std::cin
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:146,
                 from a.cc:1:
/usr/include/c++/14/iostream:62:18: note: 'std::cin' declared here
   62 |   extern istream cin;           ///< Linked to standard input
      |                  ^~~
a.cc:12:11: error: 'N' was not declared in this scope
   12 |   cin>>H>>N;
      |           ^
a.cc:13:3: error: 'vector' was not declared in this scope
   13 |   vector<string> a(H);
      |   ^~~~~~
a.cc:13:3: note: suggested alternatives:
In file included from /usr/include/c++/14/vector:66,
                 from /usr/include/c++/14/functional:64,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:53:
/usr/include/c++/14/bits/stl_vector.h:428:11: note:   'std::vector'
  428 |     class vector : protected _Vector_base<_Tp, _Alloc>
      |           ^~~~~~
/usr/include/c++/14/vector:93:13: note:   'std::pmr::vector'
   93 |       using vector = std::vector<_Tp, polymorphic_allocator<_Tp>>;
      |             ^~~~~~
a.cc:13:10: error: 'string' was not declared in this scope
   13 |   vector<string> a(H);
      |          ^~~~~~
a.cc:13:10: note: suggested alternatives:
In file included from /usr/include/c++/14/string:41,
                 from /usr/include/c++/14/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52:
/usr/include/c++/14/bits/stringfwd.h:77:33: note:   'std::string'
   77 |   typedef basic_string<char>    string;
      |                                 ^~~~~~
/usr/include/c++/14/string:76:11: note:   'std::pmr::string'
   76 |     using string    = basic_string<char>;
      |           ^~~~~~
a.cc:13:18: error: 'a' was not declared in this scope
   13 |   vector<string> a(H);
      |                  ^
a.cc:17:10: error: expected primary-expression before 'bool'
   17 |   vector<bool> row(H, false);
      |          ^~~~
a.cc:18:10: error: expected primary-expression before 'bool'
   18 |   vector<bool> col(W, false);
      |          ^~~~
a.cc:22:9: error: 'row' was not declared in this scope; did you mean 'pow'?
   22 |         row[i]=true;
      |         ^~~
      |         pow
a.cc:23:9: error: 'col' was not declared in this scope; did you mean 'cosl'?
   23 |         col[j]=true;
      |         ^~~
      |         cosl
a.cc:28:8: error: 'row' was not declared in this scope; did you mean 'pow'?
   28 |     if(row[i]){
      |        ^~~
      |        pow
a.cc:30:12: error: 'col' was not declared in this scope; did you mean 'cosl'?
   30 |         if(col[j]){
      |            ^~~
      |            cosl
a.cc:31:11: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   31 |           cout<<a[i][j] ;
      |           ^~~~
      |           std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:34:7: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   34 |       cout<<endl;
      |       ^~~~
      |       std::cout
/usr/include/c++/14/iostream:63:18: note: 'std::cout' declared here
   63 |   extern ostream cout;          ///< Linked to standard output
      |                  ^~~~
a.cc:34:13: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   34 |       cout<<endl;
      |             ^~~~
      |             std::endl
In file included from /usr/include/c++/14/istream:41,
                 from /usr/include/c++/14/sstream:40,
                 from /usr/include/c++/14/complex:45,
                 from /usr/include/c++/14/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:127:
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~