#include <iostream>
using namespace ::std;

int main() {
    int n = 0;
    cin << n;
    if (1 < n && n < 5) {
        cout >> n* n - 1
    }
}

/sandbox/1/a.cpp: In function 'int main()':
/sandbox/1/a.cpp:7:5: error: no match for 'operator<<' (operand types are 'std::istream' {aka 'std::basic_istream<char>'} and 'int')
    7 |  cin<<n;
      |  ~~~^~~
      |  |    |
      |  |    int
      |  std::istream {aka std::basic_istream<char>}
/sandbox/1/a.cpp:7:5: note: candidate: 'operator<<(int, int)' (built-in)
    7 |  cin<<n;
      |  ~~~^~~
/sandbox/1/a.cpp:7:5: note:   no known conversion for argument 1 from 'std::istream' {aka 'std::basic_istream<char>'} to 'int'
In file included from /usr/include/c++/10/bits/basic_string.h:48,
                 from /usr/include/c++/10/string:55,
                 from /usr/include/c++/10/bits/locale_classes.h:40,
                 from /usr/include/c++/10/bits/ios_base.h:41,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/ostream:38,
                 from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/string_view:622:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, std::basic_string_view<_CharT, _Traits>)'
  622 |     operator<<(basic_ostream<_CharT, _Traits>& __os,
      |     ^~~~~~~~
/usr/include/c++/10/string_view:622:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/string:55,
                 from /usr/include/c++/10/bits/locale_classes.h:40,
                 from /usr/include/c++/10/bits/ios_base.h:41,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/ostream:38,
                 from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/bits/basic_string.h:6458:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, const std::__cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 6458 |     operator<<(basic_ostream<_CharT, _Traits>& __os,
      |     ^~~~~~~~
/usr/include/c++/10/bits/basic_string.h:6458:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/bits/ios_base.h:46,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/ostream:38,
                 from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/system_error:262:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, const std::error_code&)'
  262 |     operator<<(basic_ostream<_CharT, _Traits>& __os, const error_code& __e)
      |     ^~~~~~~~
/usr/include/c++/10/system_error:262:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/ostream:506:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, _CharT)'
  506 |     operator<<(basic_ostream<_CharT, _Traits>& __out, _CharT __c)
      |     ^~~~~~~~
/usr/include/c++/10/ostream:506:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/ostream:511:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, char)'
  511 |     operator<<(basic_ostream<_CharT, _Traits>& __out, char __c)
      |     ^~~~~~~~
/usr/include/c++/10/ostream:511:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/ostream:517:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, char)'
  517 |     operator<<(basic_ostream<char, _Traits>& __out, char __c)
      |     ^~~~~~~~
/usr/include/c++/10/ostream:517:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/ostream:523:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, signed char)'
  523 |     operator<<(basic_ostream<char, _Traits>& __out, signed char __c)
      |     ^~~~~~~~
/usr/include/c++/10/ostream:523:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/ostream:528:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, unsigned char)'
  528 |     operator<<(basic_ostream<char, _Traits>& __out, unsigned char __c)
      |     ^~~~~~~~
/usr/include/c++/10/ostream:528:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/ostream:589:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, const _CharT*)'
  589 |     operator<<(basic_ostream<_CharT, _Traits>& __out, const _CharT* __s)
      |     ^~~~~~~~
/usr/include/c++/10/ostream:589:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/ostream:784,
                 from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/bits/ostream.tcc:321:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_ostream<_CharT, _Traits>& std::operator<<(std::basic_ostream<_CharT, _Traits>&, const char*)'
  321 |     operator<<(basic_ostream<_CharT, _Traits>& __out, const char* __s)
      |     ^~~~~~~~
/usr/include/c++/10/bits/ostream.tcc:321:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<_CharT, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/ostream:606:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, const char*)'
  606 |     operator<<(basic_ostream<char, _Traits>& __out, const char* __s)
      |     ^~~~~~~~
/usr/include/c++/10/ostream:606:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/ostream:619:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, const signed char*)'
  619 |     operator<<(basic_ostream<char, _Traits>& __out, const signed char* __s)
      |     ^~~~~~~~
/usr/include/c++/10/ostream:619:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/ostream:624:5: note: candidate: 'template<class _Traits> std::basic_ostream<char, _Traits>& std::operator<<(std::basic_ostream<char, _Traits>&, const unsigned char*)'
  624 |     operator<<(basic_ostream<char, _Traits>& __out, const unsigned char* __s)
      |     ^~~~~~~~
/usr/include/c++/10/ostream:624:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:7:7: note:   'std::istream' {aka 'std::basic_istream<char>'} is not derived from 'std::basic_ostream<char, _Traits>'
    7 |  cin<<n;
      |       ^
In file included from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/ostream:773:5: note: candidate: 'template<class _Ostream, class _Tp> typename std::enable_if<std::__and_<std::__not_<std::is_lvalue_reference<_Tp> >, std::__is_convertible_to_basic_ostream<_Ostream>, std::__is_insertable<typename std::__is_convertible_to_basic_ostream<_Tp>::__ostream_type, const _Tp&, void> >::value, typename std::__is_convertible_to_basic_ostream<_Tp>::__ostream_type>::type std::operator<<(_Ostream&&, const _Tp&)'
  773 |     operator<<(_Ostream&& __os, const _Tp& __x)
      |     ^~~~~~~~
/usr/include/c++/10/ostream:773:5: note:   template argument deduction/substitution failed:
/usr/include/c++/10/ostream: In substitution of 'template<class _Ostream, class _Tp> typename std::enable_if<std::__and_<std::__not_<std::is_lvalue_reference<_Tp> >, std::__is_convertible_to_basic_ostream<_Ostream>, std::__is_insertable<typename std::__is_convertible_to_basic_ostream<_Tp>::__ostream_type, const _Tp&, void> >::value, typename std::__is_convertible_to_basic_ostream<_Tp>::__ostream_type>::type std::operator<<(_Ostream&&, const _Tp&) [with _Ostream = std::basic_istream<char>&; _Tp = int]':
/sandbox/1/a.cpp:7:7:   required from here
/usr/include/c++/10/ostream:773:5: error: no type named 'type' in 'struct std::enable_if<false, void>'
/sandbox/1/a.cpp:10:6: error: no match for 'operator>>' (operand types are 'std::ostream' {aka 'std::basic_ostream<char>'} and 'int')
   10 |  cout>>n*n-1
      |  ~~~~^~~~~~~
      |  |        |
      |  |        int
      |  std::ostream {aka std::basic_ostream<char>}
/sandbox/1/a.cpp:10:6: note: candidate: 'operator>>(int, int)' (built-in)
   10 |  cout>>n*n-1
      |  ~~~~^~~~~~~
/sandbox/1/a.cpp:10:6: note:   no known conversion for argument 1 from 'std::ostream' {aka 'std::basic_ostream<char>'} to 'int'
In file included from /usr/include/c++/10/string:56,
                 from /usr/include/c++/10/bits/locale_classes.h:40,
                 from /usr/include/c++/10/bits/ios_base.h:41,
                 from /usr/include/c++/10/ios:42,
                 from /usr/include/c++/10/ostream:38,
                 from /usr/include/c++/10/iostream:39,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/bits/basic_string.tcc:1476:5: note: candidate: 'template<class _CharT, class _Traits, class _Alloc> std::basic_istream<_CharT, _Traits>& std::operator>>(std::basic_istream<_CharT, _Traits>&, std::__cxx11::basic_string<_CharT, _Traits, _Allocator>&)'
 1476 |     operator>>(basic_istream<_CharT, _Traits>& __in,
      |     ^~~~~~~~
/usr/include/c++/10/bits/basic_string.tcc:1476:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:10:12: note:   'std::ostream' {aka 'std::basic_ostream<char>'} is not derived from 'std::basic_istream<_CharT, _Traits>'
   10 |  cout>>n*n-1
      |            ^
In file included from /usr/include/c++/10/istream:991,
                 from /usr/include/c++/10/iostream:40,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/bits/istream.tcc:931:5: note: candidate: 'template<class _CharT, class _Traits> std::basic_istream<_CharT, _Traits>& std::operator>>(std::basic_istream<_CharT, _Traits>&, _CharT&)'
  931 |     operator>>(basic_istream<_CharT, _Traits>& __in, _CharT& __c)
      |     ^~~~~~~~
/usr/include/c++/10/bits/istream.tcc:931:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:10:12: note:   'std::ostream' {aka 'std::basic_ostream<char>'} is not derived from 'std::basic_istream<_CharT, _Traits>'
   10 |  cout>>n*n-1
      |            ^
In file included from /usr/include/c++/10/iostream:40,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/istream:756:5: note: candidate: 'template<class _Traits> std::basic_istream<char, _Traits>& std::operator>>(std::basic_istream<char, _Traits>&, unsigned char&)'
  756 |     operator>>(basic_istream<char, _Traits>& __in, unsigned char& __c)
      |     ^~~~~~~~
/usr/include/c++/10/istream:756:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:10:12: note:   'std::ostream' {aka 'std::basic_ostream<char>'} is not derived from 'std::basic_istream<char, _Traits>'
   10 |  cout>>n*n-1
      |            ^
In file included from /usr/include/c++/10/iostream:40,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/istream:761:5: note: candidate: 'template<class _Traits> std::basic_istream<char, _Traits>& std::operator>>(std::basic_istream<char, _Traits>&, signed char&)'
  761 |     operator>>(basic_istream<char, _Traits>& __in, signed char& __c)
      |     ^~~~~~~~
/usr/include/c++/10/istream:761:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:10:12: note:   'std::ostream' {aka 'std::basic_ostream<char>'} is not derived from 'std::basic_istream<char, _Traits>'
   10 |  cout>>n*n-1
      |            ^
In file included from /usr/include/c++/10/istream:991,
                 from /usr/include/c++/10/iostream:40,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/bits/istream.tcc:963:5: note: candidate: 'template<class _CharT2, class _Traits2> std::basic_istream<_CharT, _Traits>& std::operator>>(std::basic_istream<_CharT, _Traits>&, _CharT2*)'
  963 |     operator>>(basic_istream<_CharT, _Traits>& __in, _CharT* __s)
      |     ^~~~~~~~
/usr/include/c++/10/bits/istream.tcc:963:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:10:12: note:   'std::ostream' {aka 'std::basic_ostream<char>'} is not derived from 'std::basic_istream<_CharT, _Traits>'
   10 |  cout>>n*n-1
      |            ^
In file included from /usr/include/c++/10/iostream:40,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/istream:803:5: note: candidate: 'template<class _Traits> std::basic_istream<char, _Traits>& std::operator>>(std::basic_istream<char, _Traits>&, unsigned char*)'
  803 |     operator>>(basic_istream<char, _Traits>& __in, unsigned char* __s)
      |     ^~~~~~~~
/usr/include/c++/10/istream:803:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:10:12: note:   'std::ostream' {aka 'std::basic_ostream<char>'} is not derived from 'std::basic_istream<char, _Traits>'
   10 |  cout>>n*n-1
      |            ^
In file included from /usr/include/c++/10/iostream:40,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/istream:808:5: note: candidate: 'template<class _Traits> std::basic_istream<char, _Traits>& std::operator>>(std::basic_istream<char, _Traits>&, signed char*)'
  808 |     operator>>(basic_istream<char, _Traits>& __in, signed char* __s)
      |     ^~~~~~~~
/usr/include/c++/10/istream:808:5: note:   template argument deduction/substitution failed:
/sandbox/1/a.cpp:10:12: note:   'std::ostream' {aka 'std::basic_ostream<char>'} is not derived from 'std::basic_istream<char, _Traits>'
   10 |  cout>>n*n-1
      |            ^
In file included from /usr/include/c++/10/iostream:40,
                 from /sandbox/1/a.cpp:1:
/usr/include/c++/10/istream:980:5: note: candidate: 'template<class _Istream, class _Tp> typename std::enable_if<std::__and_<std::__not_<std::is_lvalue_reference<_Tp> >, std::__is_convertible_to_basic_istream<_Istream>, std::__is_extractable<typename std::__is_convertible_to_basic_istream<_Tp>::__istream_type, _Tp&&, void> >::value, typename std::__is_convertible_to_basic_istream<_Tp>::__istream_type>::type std::operator>>(_Istream&&, _Tp&&)'
  980 |     operator>>(_Istream&& __is, _Tp&& __x)
      |     ^~~~~~~~
/usr/include/c++/10/istream:980:5: note:   template argument deduction/substitution failed:
/usr/include/c++/10/istream: In substitution of 'template<class _Istream, class _Tp> typename std::enable_if<std::__and_<std::__not_<std::is_lvalue_reference<_Tp> >, std::__is_convertible_to_basic_istream<_Istream>, std::__is_extractable<typename std::__is_convertible_to_basic_istream<_Tp>::__istream_type, _Tp&&, void> >::value, typename std::__is_convertible_to_basic_istream<_Tp>::__istream_type>::type std::operator>>(_Istream&&, _Tp&&) [with _Istream = std::basic_ostream<char>&; _Tp = int]':
/sandbox/1/a.cpp:10:12:   required from here
/usr/include/c++/10/istream:980:5: error: no type named 'type' in 'struct std::enable_if<false, void>'