Compilare: main.cpp: In function 'void Sort()': main.cpp:28:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1;i < pol.size();++i) ~~^~~~~~~~~~~~ main.cpp: In function 'void convex_hull()': main.cpp:40:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 2;i < pol.size();++i) ~~^~~~~~~~~~~~