How does a regular expression match an incremental number?

This article describes in detail how regular expressions match a 6-digit numeric format. How to match an incremental number with a regular expression:

How does a regular expression match a 6-digit numeric format?
123123
234234
345345

1,

/^ (123 | 234 | 345 | 456 | 678 | 789) \ 1 $/g

2,

Var aabbcc =/^ (? :( \ D) \ 1) + $/; var abababab =/(\ d {2}) \ 1 + $/; var abcabc =/^ (\ d {3 }) \ 1 + $/; var aaabbb =/^ (? :( \ D) \ 1 \ 1) + $ /;

The above is how the regular expression matches the content of the incremental number. For more information, see The PHP Chinese website (www.php1.cn )!