/in/foo.cc: In function 'double getArea(Polygom)':
/in/foo.cc:43:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 1 ; i < a.size() - 1 ; i++)
                     ~~^~~~~~~~~~~~~~
/in/foo.cc: In function 'Polygom andrewScan(Polygom)':
/in/foo.cc:62:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 2 ; i < s.size() ; i++)
                     ~~^~~~~~~~~~
/in/foo.cc:76:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 1 ; i < l.size() - 1 ; i++) u.push_back(l[i]);
                     ~~^~~~~~~~~~~~~~