Compilare: user.cpp: In function ‘int main()’: user.cpp:169:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < convex.size(); i++) ^ user.cpp:172:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < convex.size(); i++) ^ user.cpp:173:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = i + 1; j < convex.size(); j++) ^ user.cpp:160:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dmg.in", "r", stdin); ^ user.cpp:161:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dmg.out", "w", stdout); ^ user.cpp:163:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:165:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf %lf", &p[i].x, &p[i].y); ^