假设我有这种文件,其中包含互联网流量信息(文件包含无限数量的字符串):
startTime sourceIP destinationIP
2015-03-31 08:47:27.671 10.0.26.48 10.0.26.255
2015-03-31 08:47:28.108 10.50.26.180 10.90.26.255
2015-03-31 08:47:35.015 10.0.26.74 255.255.255.255
...
2015-03-31 16:18:25.365 196.0.26.13 224.0.0.252
2015-03-31 16:18:32.718 10.46.26.13 224.0.0.252
2015-03-31 16:18:46.941 188.0.26.98 177.0.26.255
2015-03-31 16:18:58.336 10.0.26.57 10.0.26.255
2015-03-31 15:53:37.451 50.0.26.13 224.0.0.252
2015-03-31 15:53:55.086 10.0.26.13 40.30.0.252
2015-03-31 15:53:55.097 128.0.26.13 224.0.0.252
...
2015-04-01 22:38:43.500 192.168.0.109 78.57.218.154
2015-04-01 22:38:43.500 213.159.38.184 192.168.0.109
2015-04-01 22:38:46.359 178.250.32.43 192.168.0.109
2015-04-01 22:38:53.269 213.159.38.184 192.168.0.109
2015-04-01 22:38:53.269 192.168.0.109 213.159.38.184
2015-04-01 22:39:14.995 54.83.28.184 192.168.0.109
我想要做的是确定天气新出现的 IP 地址没有在上面的任何地方列出,所以我可以将它们标记为新的并将它们保存在其他地方。即使它们在最近几天出现,我也会认为它们是新的。
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