/in/foo.cc:3:5: error: cannot declare '::main' to be a global variable
 int main{
     ^~~~
/in/foo.cc:4:13: error: invalid operands of types '<unresolved overloaded function type>' and 'int' to binary 'operator<<'
 cout<<4<endl<<6;
         ~~~~^~~
/in/foo.cc:4:16: error: expected '}' before ';' token
 cout<<4<endl<<6;
                ^
/in/foo.cc:5:1: error: expected unqualified-id before 'return'
 return 0;
 ^~~~~~
/in/foo.cc:6:1: error: expected declaration before '}' token
 }
 ^