Compilare: user.cpp: In function ‘void find_points(circle, circle)’: user.cpp:55:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < points.size() && !flag; i++) ^ user.cpp:68:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < points.size() && flag != 3; i++) { ^ user.cpp: In function ‘int main()’: user.cpp:89:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cerc.in","r",stdin); ^ user.cpp:90:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cerc.out","w",stdout); ^