Compilare: user.c: In function ‘main’: user.c:17:9: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d %d", &N, &M, &K); ^ user.c:19:11: warning: ignoring return value of ‘fscanf’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d %d", &stack[i].l, &stack[i].r); ^ user.c:31:10: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("stergeri.out", "w", stdout); ^