Compilare: user.cpp: In function ‘void read_()’: user.cpp:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp: In function ‘void print_v(std::vector<Point, std::allocator<Point> >)’: user.cpp:74: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘double solve_mid(double, std::vector<Point, std::allocator<Point> >)’: user.cpp:81: warning: comparison between signed and unsigned integer expressions user.cpp:82: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:114: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:115: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result