Regular Expressions 101

Pro

1st Alternative(?<=[^\?]\?{3})\d+

Positive Lookbehind(?<=[^\?]\?{3})

Negated Character Class[^\?]

\?the literal ? (63₁₀ / 77₈ / 3F₁₆)

\?{3}the literal ? (63₁₀ / 77₈ / 3F₁₆) , repeated exactly 3 times

\d+a digit, repeated at least once

2nd Alternative\d+(?=\?{3}(?:[^\?]|$))

\d+a digit, repeated at least once

Positive Lookahead(?=\?{3}(?:[^\?]|$))

\?{3}the literal ? (63₁₀ / 77₈ / 3F₁₆) , repeated exactly 3 times

Non-Capturing Group(?:[^\?]|$)

1st Alternative[^\?]

Negated Character Class[^\?]

\?the literal ? (63₁₀ / 77₈ / 3F₁₆)

2nd Alternative$

$end of line

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

(?<=[^\?]\?{3})\d+|\d+(?=\?{3}(?:[^\?]|$))

New

acc5???7???7ss?3rr1??5
5???abc???3
???1x5????abc2???xyz????1abc???3abc
???1x5abc10???
????1x5abc10????

acc5???7???7ss?3rr1??5
5???abc???3
???1x5????abc2???xyz????1abc???3abc
???1x5abc10???
????1x5abc10????