Language: C++

#include <string>
#include <iostream>
 
int main(int argc, char* argv[]) {
  std::string str;
  str << std::cin;
  std::cout << (atoi(str.substr(4, 2).c_str) <= 4) ? "Heisei" : "TBD";
  return 0;
}


Compiler output:
a.cc: In function 'int main(int, char**)':
a.cc:6:7: error: no match for 'operator<<' (operand types are 'std::string' {aka 'std::__cxx11::basic_string<char>'} and 'std::istream' {aka 'std::basic_istream<char>'})
    6 |   str << std::cin;
      |   ~~~ ^~ ~~~~~~~~
      |   |           |
      |   |           std::istream {aka std::basic_istream<char>}
      |   std::string {aka std::__cxx11::basic_string<char>}
In file included from /usr/include/c++/14/bits/basic_string.h:47,
                 from /usr/include/c++/14/string:54,
                 from a.cc:1:
/usr/include/c++/14/string_view:763:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(basic_ostream<_CharT, _Traits>&, basic_string_view<_CharT, _Traits>)'
  763 |     operator<<(basic_ostream<_CharT, _Traits>& __os,
      |     ^~~~~~~~
/usr/include/c++/14/string_view:763:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/bits/basic_string.h:4077:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::basic_ostream<_CharT, _Traits>& std::operator<<(basic_ostream<_CharT, _Traits>&, const __cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 4077 |     operator<<(basic_ostream<_CharT, _Traits>& __os,
      |     ^~~~~~~~
/usr/include/c++/14/bits/basic_string.h:4077:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    6 |   str << std::cin;
      |               ^~~
In file included from /usr/include/c++/14/bits/memory_resource.h:38,
                 from /usr/include/c++/14/string:68:
/usr/include/c++/14/cstddef:125:5: note: candidate: 'template<class _IntegerType> constexpr std::__byte_op_t<_IntegerType> std::operator<<(byte, _IntegerType)'
  125 |     operator<<(byte __b, _IntegerType __shift) noexcept
      |     ^~~~~~~~
/usr/include/c++/14/cstddef:125:5: note:   template argument deduction/substitution failed:
a.cc:6:3: note:   cannot convert 'str' (type 'std::string' {aka 'std::__cxx11::basic_string<char>'}) to type 'std::byte'
    6 |   str << std::cin;
      |   ^~~
In file included from /usr/include/c++/14/bits/ios_base.h:46,
                 from /usr/include/c++/14/ios:44,
                 from /usr/include/c++/14/ostream:40,
                 from /usr/include/c++/14/iostream:41,
                 from a.cc:2:
/usr/include/c++/14/system_error:339:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(basic_ostream<_CharT, _Traits>&, const error_code&)'
  339 |     operator<<(basic_ostream<_CharT, _Traits>& __os, const error_code& __e)
      |     ^~~~~~~~
/usr/include/c++/14/system_error:339:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/ostream:563:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(basic_ostream<_CharT, _Traits>&, _CharT)'
  563 |     operator<<(basic_ostream<_CharT, _Traits>& __out, _CharT __c)
      |     ^~~~~~~~
/usr/include/c++/14/ostream:563:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/ostream:573:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(basic_ostream<_CharT, _Traits>&, char)'
  573 |     operator<<(basic_ostream<_CharT, _Traits>& __out, char __c)
      |     ^~~~~~~~
/usr/include/c++/14/ostream:573:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/ostream:579:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(basic_ostream<char, _Traits>&, char)'
  579 |     operator<<(basic_ostream<char, _Traits>& __out, char __c)
      |     ^~~~~~~~
/usr/include/c++/14/ostream:579:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/ostream:590:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(basic_ostream<char, _Traits>&, signed char)'
  590 |     operator<<(basic_ostream<char, _Traits>& __out, signed char __c)
      |     ^~~~~~~~
/usr/include/c++/14/ostream:590:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/ostream:595:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(basic_ostream<char, _Traits>&, unsigned char)'
  595 |     operator<<(basic_ostream<char, _Traits>& __out, unsigned char __c)
      |     ^~~~~~~~
/usr/include/c++/14/ostream:595:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/ostream:654:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(basic_ostream<_CharT, _Traits>&, const _CharT*)'
  654 |     operator<<(basic_ostream<_CharT, _Traits>& __out, const _CharT* __s)
      |     ^~~~~~~~
/usr/include/c++/14/ostream:654:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    6 |   str << std::cin;
      |               ^~~
In file included from /usr/include/c++/14/ostream:1022:
/usr/include/c++/14/bits/ostream.tcc:307:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(basic_ostream<_CharT, _Traits>&, const char*)'
  307 |     operator<<(basic_ostream<_CharT, _Traits>& __out, const char* __s)
      |     ^~~~~~~~
/usr/include/c++/14/bits/ostream.tcc:307:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/ostream:671:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(basic_ostream<char, _Traits>&, const char*)'
  671 |     operator<<(basic_ostream<char, _Traits>& __out, const char* __s)
      |     ^~~~~~~~
/usr/include/c++/14/ostream:671:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/ostream:684:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(basic_ostream<char, _Traits>&, const signed char*)'
  684 |     operator<<(basic_ostream<char, _Traits>& __out, const signed char* __s)
      |     ^~~~~~~~
/usr/include/c++/14/ostream:684:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/ostream:689:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(basic_ostream<char, _Traits>&, const unsigned char*)'
  689 |     operator<<(basic_ostream<char, _Traits>& __out, const unsigned char* __s)
      |     ^~~~~~~~
/usr/include/c++/14/ostream:689:5: note:   template argument deduction/substitution failed:
a.cc:6:15: note:   'std::string' {aka 'std::__cxx11::basic_string<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/ostream:810:5: note: candidate: 'template<class _Ostream, class _Tp> _Ostream&& std::operator<<(_Ostream&&, const _Tp&)'
  810 |     operator<<(_Ostream&& __os, const _Tp& __x)
      |     ^~~~~~~~
/usr/include/c++/14/ostream:810:5: note:   template argument deduction/substitution failed:
/usr/include/c++/14/ostream: In substitution of 'template<class _Ostream, class _Tp> _Ostream&& std::operator<<(_Ostream&&, const _Tp&) [with _Ostream = std::__cxx11::basic_string<char>&; _Tp = std::basic_istream<char>]':
a.cc:6:15:   required from here
    6 |   str << std::cin;
      |               ^~~
/usr/include/c++/14/ostream:810:5: error: no type named 'type' in 'struct std::enable_if<false, void>'
  810 |     operator<<(_Ostream&& __os, const _Tp& __x)
      |     ^~~~~~~~
a.cc:7:39: error: invalid use of non-static member function 'const _CharT* std::__cxx11::basic_string<_CharT, _Traits, _Alloc>::c_str() const [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>]'
    7 |   std::cout << (atoi(str.substr(4, 2).c_str) <= 4) ? "Heisei" : "TBD";
      |                      ~~~~~~~~~~~~~~~~~^~~~~
/usr/include/c++/14/bits/basic_string.h:2640:7: note: declared here
 2640 |       c_str() const _GLIBCXX_NOEXCEPT
      |       ^~~~~