Compilare: user.c:19:12: warning: conflicting types for built-in function ‘rint’ static int rint(void) ^~~~ user.c: In function ‘main’: user.c:35:12: warning: variable ‘n’ set but not used [-Wunused-but-set-variable] int i, n, m, x, u, v; ^ user.c:37:5: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("reinvent.in", "r", stdin); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ user.c:38:5: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("reinvent.out", "w", stdout); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ user.c:40:5: warning: ignoring return value of ‘read’, declared with attribute warn_unused_result [-Wunused-result] read(STDIN_FILENO, buf, BMAX); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~