pineapple0122@lchs_online_judge:~$ ssh 163.16.72.231 ssh: connect to host 163.16.72.231 port 22: Connection refused pineapple0122@lchs_online_judge:~$ ssh 163.16.72.231:88 ssh: Could not resolve hostname 163.16.72.231:88: Name or service not known pineapple0122@lchs_online_judge:~$ ssh 163.16.72.231:8088 ssh: Could not resolve hostname 163.16.72.231:8088: Name or service not known pineapple0122@lchs_online_judge:~$ ssh 163.16.72.231:8868 ssh: Could not resolve hostname 163.16.72.231:8868: Name or service not known pineapple0122@lchs_online_judge:~$