/in/foo.cc: In member function 'void Big::init(std::__cxx11::string&)':
/in/foo.cc:15:9: warning: unused variable 'j' [-Wunused-variable]
   int i,j,k,len=s.size();
         ^
/in/foo.cc: In member function 'void Big::Add(Big&)':
/in/foo.cc:23:9: warning: unused variable 'j' [-Wunused-variable]
   int i,j,k;cur=max(cur,o.cur);
         ^
/in/foo.cc:23:11: warning: unused variable 'k' [-Wunused-variable]
   int i,j,k;cur=max(cur,o.cur);
           ^
/in/foo.cc: In member function 'void Big::Sub(Big&)':
/in/foo.cc:32:9: warning: unused variable 'j' [-Wunused-variable]
   int i,j,k;
         ^
/in/foo.cc:32:11: warning: unused variable 'k' [-Wunused-variable]
   int i,j,k;
           ^
/in/foo.cc: In member function 'void Big::Print()':
/in/foo.cc:49:11: warning: unused variable 'k' [-Wunused-variable]
   int i,j,k;ll t;
           ^
/in/foo.cc:49:16: warning: unused variable 't' [-Wunused-variable]
   int i,j,k;ll t;
                ^