Regular Expressions 101

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/
(1(01*0)*1(11)*0*)+
/
gmi
1st Capturing Group
(1(01*0)*1(11)*0*)+
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
1 matches the character 1 with index 4910 (3116 or 618) literally (case insensitive)
2nd Capturing Group
(01*0)*
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
0 matches the character 0 with index 4810 (3016 or 608) literally (case insensitive)
1
matches the character 1 with index 4910 (3116 or 618) literally (case insensitive)
0 matches the character 0 with index 4810 (3016 or 608) literally (case insensitive)
1 matches the character 1 with index 4910 (3116 or 618) literally (case insensitive)
3rd Capturing Group
(11)*
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
A repeated capturing group will only capture the last iteration. Put a capturing group around the repeated group to capture all iterations or use a non-capturing group instead if you're not interested in the data
11
matches the characters 11 literally (case insensitive)
0
matches the character 0 with index 4810 (3016 or 608) literally (case insensitive)
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.

Regular Expression
No Match

/
/
gmi

Test String