Regular Expressions 101

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^ asserts position at start of the string
1st Capturing Group
+ 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
matches the character a with index 9710 (6116 or 1418) literally (case sensitive)
$ asserts position at the end of the string
Your regular expression does not match the subject string.

Regular Expression
No Match


Test String