Regular Expressions 101

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/
^(.*)(\/[0-9]+\/[a-z]+\-[a-z]+\/?.*)\/?$
/
gmi
^ asserts position at start of a line
1st Capturing Group
(.*)
.
matches any character (except for line terminators)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
2nd Capturing Group
(\/[0-9]+\/[a-z]+\-[a-z]+\/?.*)
\/ matches the character / with index 4710 (2F16 or 578) literally (case insensitive)
Match a single character present in the list below
[0-9]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case insensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case insensitive)
Match a single character present in the list below
[a-z]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case insensitive)
\- matches the character - with index 4510 (2D16 or 558) literally (case insensitive)
Match a single character present in the list below
[a-z]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
a-z matches a single character in the range between a (index 97) and z (index 122) (case insensitive)
\/
matches the character / with index 4710 (2F16 or 578) literally (case insensitive)
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
.
matches any character (except for line terminators)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
\/
matches the character / with index 4710 (2F16 or 578) literally (case insensitive)
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
$ asserts position at the end of a line
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
i modifier: insensitive. Case insensitive match (ignores case of [a-zA-Z])
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gmi

Test String