Compilare: user.cpp: In function ‘std::vector<std::pair<double, double>, std::allocator<std::pair<double, double> > > convexHull(std::vector<std::pair<double, double>, std::allocator<std::pair<double, double> > >)’: user.cpp:28: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘double ariePoligon(std::vector<std::pair<double, double>, std::allocator<std::pair<double, double> > >)’: user.cpp:46: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘double solve(int)’: user.cpp:97: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:111: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:112: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:114: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:117: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:119: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result