运行 ID: 31030

Main.cc:1:21: warning: extra tokens at end of #include directive
 #include  using namespace std
                     ^~~~~
Main.cc: In function ‘int main()’:
Main.cc:2:24: error: ‘cin’ was not declared in this scope
 int main() { int a, b; cin >> a >> b
                        ^~~
Main.cc:2:24: 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
                  ^~~