PING ip-www.shzhongkao.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=59 time=5.10 ms
64 bytes from 104.21.9.108 (104.21.9.108): icmp_seq=2 ttl=59 time=4.67 ms
64 bytes from 104.21.9.108 (104.21.9.108): icmp_seq=3 ttl=59 time=4.85 ms

--- ip-www.shzhongkao.icoc.cc ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2002ms
rtt min/avg/max/mdev = 4.676/4.877/5.106/0.194 ms