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:45:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 2;i < pol.size();++i) ~~^~~~~~~~~~~~ main.cpp:57:10: warning: 'area' may be used uninitialized in this function [-Wmaybe-uninitialized] area += (st[i].x * st[i + 1].y - st[i].y * st[i + 1].x); ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~