Compilare: user.cpp: In function ‘int main()’: user.cpp:24:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen (FIN, "r", stdin); ^ user.cpp:25:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen (FOU, "w", stdout); ^ user.cpp:27:43: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%lf %lf %d", A + 0, B + 0, &N); ^ user.cpp:29:51: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%lf %lf %d", A + i, B + i, dp + i); ^