芦笋汤的做法大全:各位好心人，谁能帮帮小弟，帮我判断两个ip地址是否有效

第2个

Microsoft Windows XP [版本 5.1.2600]
(C) 版权所有 1985-2001 Microsoft Corp.

C:\Documents and Settings\Administrator>ping 202.194.16.255

Pinging 202.194.16.255 with 32 bytes of data:

Reply from 202.194.0.182: bytes=32 time=1794ms TTL=238
Reply from 202.194.0.182: bytes=32 time=1025ms TTL=238
Request timed out.
Reply from 202.194.0.182: bytes=32 time=934ms TTL=238

Ping statistics for 202.194.16.255:
Packets: Sent = 4, Received = 3, Lost = 1 (25% loss),
Approximate round trip times in milli-seconds:
Minimum = 934ms, Maximum = 1794ms, Average = 1251ms

C:\Documents and Settings\Administrator>ping 202.194.16.0

Pinging 202.194.16.0 with 32 bytes of data:

Request timed out.
Reply from 202.194.0.182: bytes=32 time=930ms TTL=238
Reply from 202.194.0.182: bytes=32 time=1078ms TTL=238
Reply from 202.194.0.182: bytes=32 time=1023ms TTL=238

Ping statistics for 202.194.16.0:
Packets: Sent = 4, Received = 3, Lost = 1 (25% loss),
Approximate round trip times in milli-seconds:
Minimum = 930ms, Maximum = 1078ms, Average = 1010ms

C:\Documents and Settings\Administrator>

两个ip都是无效的!这两个都是C类IP,也就是说他的最后10进制数是他的主机地址。而在网络中主机地址不能是全0，或全1（这里是转化为2进制）。
A类地址：1-127开头
B类地址：128-191
c类地址：192-224
具体为什么这样划。你在看下书。这里不好详述

202.194.16.255，自己在电脑上试试，最后数字不能为0

0也不是.
255也不是.

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