Language: C++

#include<bits/stdc++.h>
using namespace sdt;
int main() {
	char a;
	cin >> a;
	if (a == 'a') {
		cout << "vowel" << endl;
	}
	else if (a == 'i') {
		cout << "vowel" << endl;
	}
	else if (a == 'u') {
		cout << "vowel" << endl;
	}
	else if (a == 'e') {
		cout << "vowel" << endl;
	}
	else if (a == 'o') {
		cout << "vowel" << endl;
	}
	else {
		cout << "consonant" << endl;
	}
	return 0;
}

Compiler output:
a.cc:2:17: error: 'sdt' is not a namespace-name
    2 | using namespace sdt;
      |                 ^~~
a.cc: In function 'int main()':
a.cc:5:9: error: 'cin' was not declared in this scope; did you mean 'std::cin'?
    5 |         cin >> a;
      |         ^~~
      |         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:7:17: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
    7 |                 cout << "vowel" << 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:7:36: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
    7 |                 cout << "vowel" << 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:10:17: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   10 |                 cout << "vowel" << 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:10:36: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   10 |                 cout << "vowel" << endl;
      |                                    ^~~~
      |                                    std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:13:17: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   13 |                 cout << "vowel" << 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:13:36: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   13 |                 cout << "vowel" << endl;
      |                                    ^~~~
      |                                    std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:16:17: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   16 |                 cout << "vowel" << 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:16:36: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   16 |                 cout << "vowel" << endl;
      |                                    ^~~~
      |                                    std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:19:17: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   19 |                 cout << "vowel" << 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:19:36: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   19 |                 cout << "vowel" << endl;
      |                                    ^~~~
      |                                    std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~
a.cc:22:17: error: 'cout' was not declared in this scope; did you mean 'std::cout'?
   22 |                 cout << "consonant" << 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:22:40: error: 'endl' was not declared in this scope; did you mean 'std::endl'?
   22 |                 cout << "consonant" << endl;
      |                                        ^~~~
      |                                        std::endl
/usr/include/c++/14/ostream:744:5: note: 'std::endl' declared here
  744 |     endl(basic_ostream<_CharT, _Traits>& __os)
      |     ^~~~