Compilare: user.c:27:12: warning: conflicting types for built-in function ‘rint’ static int rint(void) ^~~~ user.c: In function ‘main’: user.c:45:5: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("reinvent.in", "r", stdin); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ user.c:46:5: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("reinvent.out", "w", stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ user.c:48:5: warning: ignoring return value of ‘read’, declared with attribute warn_unused_result [-Wunused-result] read(STDIN_FILENO, buf, BMAX); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~