Compilare: user.cpp: In function ‘int main()’: user.cpp:28:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("qtri.in", "r", stdin); ^ user.cpp:29:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("qtri.out", "w", stdout); ^ user.cpp:34:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:38:82: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf%lf%lf%lf%lf%lf%lf%lf", &x1, &x2, &y1, &y2, &z1, &z2, &t1, &t2); ^