foo.cc: In function 'int main()':
foo.cc:35:26: error: cannot convert 'std::__cxx11::basic_string<char>::iterator {aka __gnu_cxx::__normal_iterator<char*, std::__cxx11::basic_string<char> >}' to 'int' in initialization
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                          ^
foo.cc:35:31: error: no match for 'operator!=' (operand types are 'int' and 'std::__cxx11::basic_string<char>::iterator {aka __gnu_cxx::__normal_iterator<char*, std::__cxx11::basic_string<char> >}')
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                             ~~^~~~~~~~~~~~
In file included from /usr/include/c++/7/iosfwd:40:0,
                 from /usr/include/c++/7/ios:38,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/postypes.h:221:5: note: candidate: template<class _StateT> bool std::operator!=(const std::fpos<_StateT>&, const std::fpos<_StateT>&)
     operator!=(const fpos<_StateT>& __lhs, const fpos<_StateT>& __rhs)
     ^~~~~~~~
/usr/include/c++/7/bits/postypes.h:221:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::fpos<_StateT>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/bits/stl_algobase.h:64:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/stl_pair.h:461:5: note: candidate: template<class _T1, class _T2> constexpr bool std::operator!=(const std::pair<_T1, _T2>&, const std::pair<_T1, _T2>&)
     operator!=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
     ^~~~~~~~
/usr/include/c++/7/bits/stl_pair.h:461:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::pair<_T1, _T2>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/stl_iterator.h:314:5: note: candidate: template<class _Iterator> bool std::operator!=(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_Iterator>&)
     operator!=(const reverse_iterator<_Iterator>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:314:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::reverse_iterator<_Iterator>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/stl_iterator.h:352:5: note: candidate: template<class _IteratorL, class _IteratorR> bool std::operator!=(const std::reverse_iterator<_Iterator>&, const std::reverse_iterator<_IteratorR>&)
     operator!=(const reverse_iterator<_IteratorL>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:352:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::reverse_iterator<_Iterator>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/stl_iterator.h:1133:5: note: candidate: template<class _IteratorL, class _IteratorR> bool std::operator!=(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorR>&)
     operator!=(const move_iterator<_IteratorL>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:1133:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::move_iterator<_IteratorL>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/stl_iterator.h:1139:5: note: candidate: template<class _Iterator> bool std::operator!=(const std::move_iterator<_IteratorL>&, const std::move_iterator<_IteratorL>&)
     operator!=(const move_iterator<_Iterator>& __x,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:1139:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::move_iterator<_IteratorL>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/string:41:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/allocator.h:158:5: note: candidate: template<class _T1, class _T2> bool std::operator!=(const std::allocator<_CharT>&, const std::allocator<_T2>&)
     operator!=(const allocator<_T1>&, const allocator<_T2>&)
     ^~~~~~~~
/usr/include/c++/7/bits/allocator.h:158:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::allocator<_CharT>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/string:41:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/allocator.h:164:5: note: candidate: template<class _Tp> bool std::operator!=(const std::allocator<_CharT>&, const std::allocator<_CharT>&)
     operator!=(const allocator<_Tp>&, const allocator<_Tp>&)
     ^~~~~~~~
/usr/include/c++/7/bits/allocator.h:164:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::allocator<_CharT>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/string:52:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/basic_string.h:6056:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> bool std::operator!=(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)
     operator!=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/basic_string.h:6056:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/string:52:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/basic_string.h:6069:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> bool std::operator!=(const _CharT*, const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&)
     operator!=(const _CharT* __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/basic_string.h:6069:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const _CharT*' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/string:52:0,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/basic_string.h:6081:5: note: candidate: template<class _CharT, class _Traits, class _Alloc> bool std::operator!=(const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>&, const _CharT*)
     operator!=(const basic_string<_CharT, _Traits, _Alloc>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/basic_string.h:6081:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::__cxx11::basic_string<_CharT, _Traits, _Alloc>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/bits/ios_base.h:46:0,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/system_error:319:3: note: candidate: bool std::operator!=(const std::error_code&, const std::error_code&)
   operator!=(const error_code& __lhs, const error_code& __rhs) noexcept
   ^~~~~~~~
/usr/include/c++/7/system_error:319:3: note:   no known conversion for argument 1 from 'int' to 'const std::error_code&'
/usr/include/c++/7/system_error:323:3: note: candidate: bool std::operator!=(const std::error_code&, const std::error_condition&)
   operator!=(const error_code& __lhs, const error_condition& __rhs) noexcept
   ^~~~~~~~
/usr/include/c++/7/system_error:323:3: note:   no known conversion for argument 1 from 'int' to 'const std::error_code&'
/usr/include/c++/7/system_error:327:3: note: candidate: bool std::operator!=(const std::error_condition&, const std::error_code&)
   operator!=(const error_condition& __lhs, const error_code& __rhs) noexcept
   ^~~~~~~~
/usr/include/c++/7/system_error:327:3: note:   no known conversion for argument 1 from 'int' to 'const std::error_condition&'
/usr/include/c++/7/system_error:331:3: note: candidate: bool std::operator!=(const std::error_condition&, const std::error_condition&)
   operator!=(const error_condition& __lhs,
   ^~~~~~~~
/usr/include/c++/7/system_error:331:3: note:   no known conversion for argument 1 from 'int' to 'const std::error_condition&'
In file included from /usr/include/c++/7/bits/locale_facets.h:48:0,
                 from /usr/include/c++/7/bits/basic_ios.h:37,
                 from /usr/include/c++/7/ios:44,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/streambuf_iterator.h:210:5: note: candidate: template<class _CharT, class _Traits> bool std::operator!=(const std::istreambuf_iterator<_CharT, _Traits>&, const std::istreambuf_iterator<_CharT, _Traits>&)
     operator!=(const istreambuf_iterator<_CharT, _Traits>& __a,
     ^~~~~~~~
/usr/include/c++/7/bits/streambuf_iterator.h:210:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::istreambuf_iterator<_CharT, _Traits>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/vector:64:0,
                 from foo.cc:2:
/usr/include/c++/7/bits/stl_vector.h:1625:5: note: candidate: template<class _Tp, class _Alloc> bool std::operator!=(const std::vector<_Tp, _Alloc>&, const std::vector<_Tp, _Alloc>&)
     operator!=(const vector<_Tp, _Alloc>& __x, const vector<_Tp, _Alloc>& __y)
     ^~~~~~~~
/usr/include/c++/7/bits/stl_vector.h:1625:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const std::vector<_Tp, _Alloc>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/x86_64-linux-gnu/c++/7/bits/c++allocator.h:33:0,
                 from /usr/include/c++/7/bits/allocator.h:46,
                 from /usr/include/c++/7/string:41,
                 from /usr/include/c++/7/bits/locale_classes.h:40,
                 from /usr/include/c++/7/bits/ios_base.h:41,
                 from /usr/include/c++/7/ios:42,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/ext/new_allocator.h:160:5: note: candidate: template<class _Tp> bool __gnu_cxx::operator!=(const __gnu_cxx::new_allocator<_Tp>&, const __gnu_cxx::new_allocator<_Tp>&)
     operator!=(const new_allocator<_Tp>&, const new_allocator<_Tp>&)
     ^~~~~~~~
/usr/include/c++/7/ext/new_allocator.h:160:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const __gnu_cxx::new_allocator<_Tp>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/stl_iterator.h:883:5: note: candidate: template<class _Iterator, class _Container> bool __gnu_cxx::operator!=(const __gnu_cxx::__normal_iterator<_Iterator, _Container>&, const __gnu_cxx::__normal_iterator<_Iterator, _Container>&)
     operator!=(const __normal_iterator<_Iterator, _Container>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:883:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const __gnu_cxx::__normal_iterator<_Iterator, _Container>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
In file included from /usr/include/c++/7/bits/stl_algobase.h:67:0,
                 from /usr/include/c++/7/bits/char_traits.h:39,
                 from /usr/include/c++/7/ios:40,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from foo.cc:1:
/usr/include/c++/7/bits/stl_iterator.h:876:5: note: candidate: template<class _IteratorL, class _IteratorR, class _Container> bool __gnu_cxx::operator!=(const __gnu_cxx::__normal_iterator<_IteratorL, _Container>&, const __gnu_cxx::__normal_iterator<_IteratorR, _Container>&)
     operator!=(const __normal_iterator<_IteratorL, _Container>& __lhs,
     ^~~~~~~~
/usr/include/c++/7/bits/stl_iterator.h:876:5: note:   template argument deduction/substitution failed:
foo.cc:35:42: note:   mismatched types 'const __gnu_cxx::__normal_iterator<_IteratorL, _Container>' and 'int'
   for (int q = cnt.begin(); q != cnt.end(); q ++)
                                          ^
foo.cc:36:9: error: 'PVS {aka struct std::pair<std::vector<int>, std::__cxx11::basic_string<char> >}' has no member named 'push_back'
    p[i].push_back(*q - '0');
         ^~~~~~~~~
foo.cc:36:20: error: invalid type argument of unary '*' (have 'int')
    p[i].push_back(*q - '0');
                    ^
foo.cc:39:2: error: 'sort' was not declared in this scope
  sort(p, p + n, cmp);
  ^~~~
foo.cc:39:2: note: suggested alternative: 'qsort'
  sort(p, p + n, cmp);
  ^~~~
  qsort

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