Language: C++

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#include <bits/stdc++.h>
usong namespace std;

int main()
{
    string s;
    cin>>s;
    if(s[2]==s[3]&&s[4]==s[5])
    cout<<"YES"<<endl;
    else
    cout<<"NO"<<endl;

    return 0;
}


Compiler output:
a.cc:10:1: error: 'usong' does not name a type; did you mean 'ulong'?
   10 | usong namespace std;
      | ^~~~~
      | ulong
a.cc: In function 'int main()':
a.cc:14:5: error: 'string' was not declared in this scope
   14 |     string s;
      |     ^~~~~~
a.cc:14:5: 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,
                 from a.cc:9:
/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:15:5: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
   15 |     cin>>s;
      |     ^~~
      |     std::cin
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:146:
/usr/include/c++/14/iostream:62:18: note: 'std::cin' declared here
   62 |   extern istream cin;           ///< Linked to standard input
      |                  ^~~
a.cc:15:10: error: 's' was not declared in this scope
   15 |     cin>>s;
      |          ^
a.cc:17:5: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   17 |     cout<<"YES"<<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:17:18: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   17 |     cout<<"YES"<<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)
      |     ^~~~
a.cc:19:5: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   19 |     cout<<"NO"<<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:19:17: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   19 |     cout<<"NO"<<endl;
      |                 ^~~~
      |                 std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~