/in/foo.cc: In member function 'Big Big::operator+(const Big&) const':
/in/foo.cc:42:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if(g==0&&i>=s.size()&&i>=b.s.size()) break;
                      ~^~~~~~~~~~
/in/foo.cc:42:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if(g==0&&i>=s.size()&&i>=b.s.size()) break;
                                   ~^~~~~~~~~~~~
/in/foo.cc:44:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if(i<s.size()) x+=s[i];
                ~^~~~~~~~~
/in/foo.cc:45:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if(i<b.s.size()) x+=b.s[i];
                ~^~~~~~~~~~~
/in/foo.cc: In function 'std::ostream& operator<<(std::ostream&, const Big&)':
/in/foo.cc:134:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j=0;j<strlen(buf);j++) out<<buf[j];
                     ~^~~~~~~~~~~~