运行 ID: 47170

Main.cc:2:7: error: expected nested-name-specifier before ‘namesapce’
 using namesapce std;
       ^~~~~~~~~
Main.cc: In function ‘int main()’:
Main.cc:4:5: error: ‘string’ was not declared in this scope
     string n;
     ^~~~~~
Main.cc:4:5: note: suggested alternatives:
In file included from /usr/include/c++/7/iosfwd:39:0,
                 from /usr/include/c++/7/ios:38,
                 from /usr/include/c++/7/ostream:38,
                 from /usr/include/c++/7/iostream:39,
                 from Main.cc:1:
/usr/include/c++/7/bits/stringfwd.h:74:33: note:   ‘std::__cxx11::string’
   typedef basic_string    string;
                                 ^~~~~~
/usr/include/c++/7/bits/stringfwd.h:74:33: note:   ‘std::__cxx11::string’
Main.cc:5:5: error: ‘cin’ was not declared in this scope
     cin>>n;
     ^~~
Main.cc:5:5: note: suggested alternative:
In file included from Main.cc:1:0:
/usr/include/c++/7/iostream:60:18: note:   ‘std::cin’
   extern istream cin;  /// Linked to standard input
                  ^~~
Main.cc:5:10: error: ‘n’ was not declared in this scope
     cin>>n;
          ^
Main.cc:7:9: error: ‘cout’ was not declared in this scope
         cout<