Eroare de compilare: main.cpp:1:1: error: stray '##' in program ##define ff first ^~ main.cpp:1:3: error: 'define' does not name a type ##define ff first ^~~~~~ In file included from /usr/include/c++/6/cmath:43:0, from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:41, from main.cpp:5: /usr/include/c++/6/ext/type_traits.h:162:35: error: '__gnu_cxx::__is_null_pointer' declared as an 'inline' variable __is_null_pointer(std::nullptr_t) ^ /usr/include/c++/6/ext/type_traits.h:162:35: error: 'bool __gnu_cxx::__is_null_pointer' redeclared as different kind of symbol /usr/include/c++/6/ext/type_traits.h:157:5: note: previous declaration 'template<class _Type> bool __gnu_cxx::__is_null_pointer(_Type)' __is_null_pointer(_Type) ^~~~~~~~~~~~~~~~~ /usr/include/c++/6/ext/type_traits.h:162:21: error: 'nullptr_t' is not a member of 'std' __is_null_pointer(std::nullptr_t) ^~~ In file included from /usr/include/c++/6/bits/move.h:57:0, from /usr/include/c++/6/bits/nested_exception.h:40, from /usr/include/c++/6/exception:171, from /usr/include/c++/6/ios:39, from /usr/include/c++/6/istream:38, from /usr/include/c++/6/sstream:38, from /usr/include/c++/6/complex:45, from /usr/include/c++/6/ccomplex:39, from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:52, from main.cpp:5: /usr/include/c++/6/type_traits:359:31: error: 'std::size_t' has not been declared template<typename _Tp, std::size_t _Size> ^~~~~~ /usr/include/c++/6/type_traits:360:25: error: '_Size' was not declared in this scope struct is_array<_Tp[_Size]> ^~~~~ /usr/include/c++/6/type_traits:360:31: error: template argument 1 is invalid struct is_array<_Tp[_Size]> ^ /usr/include/c++/6/type_traits:558:37: error: 'nullptr_t' is not a member of 'std' struct __is_null_pointer_helper<std::nullptr_t> ^~~ /usr/include/c++/6/type_traits:558:37: note: suggested alternative: In file included from /usr/include/c++/6/cstddef:50:0, from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:45, from main.cpp:5: /usr/lib/gcc/x86_64-linux-gnu/6/include/stddef.h:436:29: note: 'nullptr_t' typedef decltype(nullptr) nullptr_t; ^~~~~~~~~ In file included from /usr/include/c++/6/bits/move.h:57:0, from /usr/include/c++/6/bits/nested_exception.h:40, Non zero exit status: 1