Compilare: user.c: In function ‘main’: user.c:137:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("paralelipiped.in", "r", stdin); ^ user.c:138:12: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("paralelipiped.out", "w", stdout); ^ user.c:141:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &t); ^ user.c:144:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &rectn); ^ user.c:149:18: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i%i%i", &rect->xmin, &rect->ymin, &rect->zmin); ^ user.c:150:18: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i%i%i", &rect->xmax, &rect->ymax, &rect->zmax); ^