Compilare: user.cpp: In function ‘bool CP(point, point)’: user.cpp:24:33: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] return (a.x<b.x)||(a.x==b.x)&&(a.y<b.y); ^ user.cpp: In function ‘void hull()’: user.cpp:7:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] #define vs v.size() ^ user.cpp:38:25: note: in expansion of macro ‘vs’ for (int i = 2; i < vs; i++) { ^ user.cpp: In function ‘void write()’: user.cpp:6:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] #define hs h.size() ^ user.cpp:64:23: note: in expansion of macro ‘hs’ for (int i = 0; i<hs; i++) ^