Compilare: user.cpp: In member function ‘i64 convex_hull_trick::get_max(i64)’: user.cpp:36:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i < h.size(); ++i) ^ user.cpp: In member function ‘convex_hull_trick::hull convex_hull_trick::merge(const convex_hull_trick::hull&, const convex_hull_trick::hull&)’: user.cpp:116:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < a.v.size() && j < b.v.size()) ^ user.cpp:116:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < a.v.size() && j < b.v.size()) ^ user.cpp:124:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < a.v.size()) ^ user.cpp:126:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (j < b.v.size()) ^ user.cpp: In function ‘int main()’: user.cpp:137:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("euro.in", "r", stdin); ^ user.cpp:138:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("euro.out", "w", stdout); ^