Compilare: user.cpp: In function ‘void read()’: user.cpp:39:49: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %lf %lf %lf\n", &n, &p1, &p2, &p3); ^ user.cpp: In function ‘int main()’: user.cpp:89:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hprob.in", "r", stdin); ^ user.cpp:90:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hprob.out", "w", stdout); ^ user.cpp:91:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^