Compilare: user.c: In function ‘main’: user.c:23:2: warning: implicit declaration of function ‘qsort’ [-Wimplicit-function-declaration] qsort(t, n, sizeof(int), cmp); ^ user.c:14:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("filme.in", "r", stdin); ^ user.c:15:9: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("filme.out", "w", stdout); ^ user.c:16:7: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld %ld", &n, &m); ^ user.c:19:8: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld %ld", &d, &t[i]); ^