foo.cc:5:9: warning: multi-character character constant [-Wmultichar]
    5 | cin>>n>>'/n';
      |         ^~~~
foo.cc: In function ‘int main()’:
foo.cc:5:7: error: no match for ‘operator>>’ (operand types are ‘std::basic_istream<char>::__istream_type’ {aka ‘std::basic_istream<char>’} and ‘int’)
    5 | cin>>n>>'/n';
      | ~~~~~~^~~~~~
      |    |    |
      |    |    int
      |    std::basic_istream<char>::__istream_type {aka std::basic_istream<char>}
In file included from iostream:42:
/nix/gcc-13.3.0/include/c++/13.3.0/istream:325:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(void*&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  325 |       operator>>(void*& __p)
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:325:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: invalid conversion from ‘int’ to ‘void*’ [-fpermissive]
    5 | cin>>n>>'/n';
      |         ^~~~
      |         |
      |         int
foo.cc:5:9: error: cannot bind rvalue ‘(void*)12142’ to ‘void*&’
/nix/gcc-13.3.0/include/c++/13.3.0/istream:224:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long double&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  224 |       operator>>(long double& __f)
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:224:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘long double&’ to a value of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:220:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(double&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  220 |       operator>>(double& __f)
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:220:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘double&’ to a value of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:216:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(float&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  216 |       operator>>(float& __f)
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:216:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘float&’ to a value of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:201:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long long unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  201 |       operator>>(unsigned long long& __n)
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:201:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘long long unsigned int&’ to a value of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:197:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long long int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  197 |       operator>>(long long& __n)
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:197:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘long long int&’ to a value of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:192:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  192 |       operator>>(unsigned long& __n)
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:192:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘long unsigned int&’ to a value of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:188:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  188 |       operator>>(long& __n)
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:188:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘long int&’ to a value of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:184:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  184 |       operator>>(unsigned int& __n)
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:184:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘unsigned int&’ to a value of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:181:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(int&) [with _CharT = char; _Traits = std::char_traits<char>]’ (near match)
  181 |       operator>>(int& __n);
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:181:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘int&’ to an rvalue of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:177:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(short unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  177 |       operator>>(unsigned short& __n)
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:177:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘short unsigned int&’ to a value of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:174:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(short int&) [with _CharT = char; _Traits = std::char_traits<char>]’ (near match)
  174 |       operator>>(short& __n);
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:174:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘short int&’ to a value of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:170:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(bool&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  170 |       operator>>(bool& __n)
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:170:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: cannot bind non-const lvalue reference of type ‘bool&’ to a value of type ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:122:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__istream_type& (*)(__istream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  122 |       operator>>(__istream_type& (*__pf)(__istream_type&))
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:122:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: invalid conversion from ‘int’ to ‘std::basic_istream<char>::__istream_type& (*)(std::basic_istream<char>::__istream_type&)’ {aka ‘std::basic_istream<char>& (*)(std::basic_istream<char>&)’} [-fpermissive]
    5 | cin>>n>>'/n';
      |         ^~~~
      |         |
      |         int
/nix/gcc-13.3.0/include/c++/13.3.0/istream:126:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__ios_type& (*)(__ios_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>; __ios_type = std::basic_ios<char>]’ (near match)
  126 |       operator>>(__ios_type& (*__pf)(__ios_type&))
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:126:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: invalid conversion from ‘int’ to ‘std::basic_istream<char>::__ios_type& (*)(std::basic_istream<char>::__ios_type&)’ {aka ‘std::basic_ios<char>& (*)(std::basic_ios<char>&)’} [-fpermissive]
    5 | cin>>n>>'/n';
      |         ^~~~
      |         |
      |         int
/nix/gcc-13.3.0/include/c++/13.3.0/istream:133:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(std::ios_base& (*)(std::ios_base&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]’ (near match)
  133 |       operator>>(ios_base& (*__pf)(ios_base&))
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:133:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: invalid conversion from ‘int’ to ‘std::ios_base& (*)(std::ios_base&)’ [-fpermissive]
    5 | cin>>n>>'/n';
      |         ^~~~
      |         |
      |         int
/nix/gcc-13.3.0/include/c++/13.3.0/istream:349:7: note: candidate: ‘std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(__streambuf_type*) [with _CharT = char; _Traits = std::char_traits<char>; __streambuf_type = std::basic_streambuf<char>]’ (near match)
  349 |       operator>>(__streambuf_type* __sb);
      |       ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:349:7: note:   conversion of argument 1 would be ill-formed:
foo.cc:5:9: error: invalid conversion from ‘int’ to ‘std::basic_istream<char>::__streambuf_type*’ {aka ‘std::basic_streambuf<char>*’} [-fpermissive]
    5 | cin>>n>>'/n';
      |         ^~~~
      |         |
      |         int
foo.cc:5:7: note: candidate: ‘operator>>(int, int)’ (built-in)
    5 | cin>>n>>'/n';
      | ~~~~~~^~~~~~
foo.cc:5:7: note:   no known conversion for argument 1 from ‘std::basic_istream<char>::__istream_type’ {aka ‘std::basic_istream<char>’} to ‘int’
In file included from /nix/gcc-13.3.0/include/c++/13.3.0/string:55,
                 from /nix/gcc-13.3.0/include/c++/13.3.0/bits/locale_classes.h:40,
                 from /nix/gcc-13.3.0/include/c++/13.3.0/bits/ios_base.h:41,
                 from /nix/gcc-13.3.0/include/c++/13.3.0/ios:44,
                 from /nix/gcc-13.3.0/include/c++/13.3.0/ostream:40,
                 from iostream:41:
/nix/gcc-13.3.0/include/c++/13.3.0/bits/basic_string.tcc:827:5: note: candidate: ‘template<class _CharT, class _Traits, class _Alloc> std::basic_istream<_CharT, _Traits>& std::operator>>(basic_istream<_CharT, _Traits>&, __cxx11::basic_string<_CharT, _Traits, _Alloc>&)’
  827 |     operator>>(basic_istream<_CharT, _Traits>& __in,
      |     ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/bits/basic_string.tcc:827:5: note:   template argument deduction/substitution failed:
foo.cc:5:9: note:   mismatched types ‘std::__cxx11::basic_string<_CharT, _Traits, _Alloc>’ and ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
In file included from /nix/gcc-13.3.0/include/c++/13.3.0/istream:1106:
/nix/gcc-13.3.0/include/c++/13.3.0/bits/istream.tcc:975:5: note: candidate: ‘template<class _CharT, class _Traits> std::basic_istream<_CharT, _Traits>& std::operator>>(basic_istream<_CharT, _Traits>&, _CharT&)’
  975 |     operator>>(basic_istream<_CharT, _Traits>& __in, _CharT& __c)
      |     ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/bits/istream.tcc:975:5: note:   template argument deduction/substitution failed:
foo.cc:5:9: note:   deduced conflicting types for parameter ‘_CharT’ (‘char’ and ‘int’)
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:846:5: note: candidate: ‘template<class _Traits> std::basic_istream<char, _Traits>& std::operator>>(basic_istream<char, _Traits>&, unsigned char&)’
  846 |     operator>>(basic_istream<char, _Traits>& __in, unsigned char& __c)
      |     ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:846:5: note:   template argument deduction/substitution failed:
foo.cc:5:9: note:   cannot convert ‘12142’ (type ‘int’) to type ‘unsigned char&’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:851:5: note: candidate: ‘template<class _Traits> std::basic_istream<char, _Traits>& std::operator>>(basic_istream<char, _Traits>&, signed char&)’
  851 |     operator>>(basic_istream<char, _Traits>& __in, signed char& __c)
      |     ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:851:5: note:   template argument deduction/substitution failed:
foo.cc:5:9: note:   cannot convert ‘12142’ (type ‘int’) to type ‘signed char&’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:893:5: note: candidate: ‘template<class _CharT, class _Traits> std::basic_istream<_CharT, _Traits>& std::operator>>(basic_istream<_CharT, _Traits>&, _CharT*)’
  893 |     operator>>(basic_istream<_CharT, _Traits>& __in, _CharT* __s)
      |     ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:893:5: note:   template argument deduction/substitution failed:
foo.cc:5:9: note:   mismatched types ‘_CharT*’ and ‘int’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:936:5: note: candidate: ‘template<class _Traits> std::basic_istream<char, _Traits>& std::operator>>(basic_istream<char, _Traits>&, unsigned char*)’
  936 |     operator>>(basic_istream<char, _Traits>& __in, unsigned char* __s)
      |     ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:936:5: note:   template argument deduction/substitution failed:
foo.cc:5:9: note:   cannot convert ‘12142’ (type ‘int’) to type ‘unsigned char*’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:942:5: note: candidate: ‘template<class _Traits> std::basic_istream<char, _Traits>& std::operator>>(basic_istream<char, _Traits>&, signed char*)’
  942 |     operator>>(basic_istream<char, _Traits>& __in, signed char* __s)
      |     ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:942:5: note:   template argument deduction/substitution failed:
foo.cc:5:9: note:   cannot convert ‘12142’ (type ‘int’) to type ‘signed char*’
    5 | cin>>n>>'/n';
      |         ^~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:1096:5: note: candidate: ‘template<class _Istream, class _Tp> _Istream&& std::operator>>(_Istream&&, _Tp&&)’
 1096 |     operator>>(_Istream&& __is, _Tp&& __x)
      |     ^~~~~~~~
/nix/gcc-13.3.0/include/c++/13.3.0/istream:1096:5: note:   template argument deduction/substitution failed:
/nix/gcc-13.3.0/include/c++/13.3.0/istream: In substitution of ‘template<class _Istream, class _Tp> _Istream&& std::operator>>(_Istream&&, _Tp&&) [with _Istream = std::basic_istream<char>&; _Tp = int]’:
foo.cc:5:9:   required from here
/nix/gcc-13.3.0/include/c++/13.3.0/istream:1096:5: error: no type named ‘type’ in ‘struct std::enable_if<false, void>’

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