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Reg
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Ex
pressions
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Regular Expression
r"
^a+(?:a(?=a*(\1?b)))+\1$
"
gm
Input 1
New
aab aaabb aaaaaaaaaaaaaaaabbb aaaabbb aaaaab aab aaabb aaaab aaaabb aaaabbb aaaaabbbb aaaaab b ab abb aabb aaaabbbb bbb aaaaaa ab abbb aaaaaabbbbbb
Extraction
aab aaabb aaaaaaaaaaaaaaaabbb aaaabbb aaaaab aab aaabb aaaab aaaabb aaaabbb aaaaabbbb aaaaab b ab abb aabb aaaabbbb bbb aaaaaa ab abbb aaaaaabbbbbb