foo.cc: In function 'int main()':
foo.cc:5:12: error: expected primary-expression before '<<' token
     printf(<<"3\n">><<"9---站台\n">><<"4\n">>);
            ^~
foo.cc:5:21: error: expected primary-expression before '<<' token
     printf(<<"3\n">><<"9---站台\n">><<"4\n">>);
                     ^~
foo.cc:5:39: error: expected primary-expression before '<<' token
     printf(<<"3\n">><<"9---站台\n">><<"4\n">>);
                                       ^~
foo.cc:5:48: error: expected primary-expression before ')' token
     printf(<<"3\n">><<"9---站台\n">><<"4\n">>);
                                                ^

自豪的采用jd5进行评测(github.com/masnn/jd5)