foo.cc: In function 'int main()':
foo.cc:33:9: error: unable to find numeric literal operator 'operator""b'
   int t=27b+(3r)%9;
         ^~~
foo.cc:33:9: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes
foo.cc:33:14: error: unable to find numeric literal operator 'operator""r'
   int t=27b+(3r)%9;
              ^~
foo.cc:33:14: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes
foo.cc:6:17: warning: unused variable 'i' [-Wunused-variable]
     int n,a[81],i=0,k=0,j=0,r=0,b=0,flag=1,t=0;
                 ^
foo.cc:6:44: warning: unused variable 't' [-Wunused-variable]
     int n,a[81],i=0,k=0,j=0,r=0,b=0,flag=1,t=0;
                                            ^

自豪的采用jd5进行评测(github.com/masnn/jd5)