I'm trying to organize ip ranges into their own type. For example, if i load this text document into a listbox:

209.170.113.9
213.161.66.236
209.170.113.31
209.170.113.7
60.254.129.78
209.170.113.24
209.170.113.17
206.16.213.8
206.16.213.14
66.77.68.17
206.16.213.8

Then I'd like my program to put everything next to its own ip range, like:

209.170.113.9
209.170.113.31
209.170.113.7
209.170.113.24
209.170.113.17
206.16.213.8
206.16.213.14
213.161.66.236
60.254.129.78
66.77.68.17

Arranging everything into its own sequence, and leaving the "non-sequenced" ones at the bottom. I'm not sure how to do this, so codes and an exampe would really be appreciated. Thanks for any help.