PING pro-www.shxueji.icoc.cc (104.21.9.108) 56(84) bytes of data.
64 bytes from 104.21.9.108 (104.21.9.108): icmp_seq=1 ttl=60 time=4.62 ms
64 bytes from 104.21.9.108 (104.21.9.108): icmp_seq=2 ttl=60 time=4.46 ms
64 bytes from 104.21.9.108 (104.21.9.108): icmp_seq=3 ttl=60 time=4.59 ms

--- pro-www.shxueji.icoc.cc ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2003ms
rtt min/avg/max/mdev = 4.469/4.564/4.628/0.088 ms