/in/foo.cc: In member function 'dts::ubigint dts::ubigint::mov(dts::ll)':
/in/foo.cc:58:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
      for (ll i=0;i<num.size();i++)
                  ~^~~~~~~~~~~
/in/foo.cc: In member function 'dts::ubigint dts::ubigint::operator*(dts::ubigint)':
/in/foo.cc:239:21: warning: unused variable 'ylen' [-Wunused-variable]
      ull xlen=len(),ylen=b.len();
                     ^~~~
/in/foo.cc: In member function 'void dts::ubigint::save(char*, dts::ull)':
/in/foo.cc:279:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if (size==-1)
         ~~~~^~~~
/in/foo.cc: In function 'void dts::bfs()':
/in/foo.cc:348:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (ll i=0;i<e[now].size();i++)
                ~^~~~~~~~~~~~~~