Compilare: user.cpp: In function ‘int main()’: user.cpp:28:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("xmoto.in", "r", stdin); ^ user.cpp:29:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("xmoto.out", "w", stdout); ^ user.cpp:31:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d", &n, &l); ^ user.cpp:33:83: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%lf%lf%lf%lf%d", &T [i].a, &T [i].b, &T [i].k, &T [i].q, &T [i].v); ^ user.cpp:50:30: warning: ‘v’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (v >= T [i - 1].v && v <= T [i].v) { ^