I must truly be obsessed with regexes, but nevermind.

If anyone's interested in a fun regex challenge, here are the specs:
Construct a SINGLE regular expression that uses only anchoring (^ and $), reptition modifiers (* and +), alternation (|), and grouping ( ( and )) that will determine whether a string consists of only 0's and 1's AND that there are the SAME number of occurrences of the substring '01' as there are '10'.

Examples:
This is a fun exercise, really. Before you start tackling it in the regex sense, though, try to explain how a match works in English (or whatever language you speak).

$_="goto+F.print+chop;\n=yhpaj";F1:eval

In reply to Fun Regex Exercise by japhy

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