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Predefined Character Sets

Computers user IP addresses to communuicate with eachother via the internet. The old protocol IP version 4 has addresses which are well readable by humans. These are four numbers from 0 to 255 which are divided by a dot.

To match all IP addresses, first you can develop the expression to match the numbers from 0 to 255.

If you do not succeed, you can use this expression and adapt it. ^(X|2[0-4]\d|25[0-5])$

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