Challenge #130: Is There an Echo in Here?

[DanielG]

Solved.  One tool (not counting input and browse 😁)

[Rob-Silk]

Solution attached below - did the one tool solution and then thought I'd have a go with a different (= not RegEx) multi-tool approach as well:

[asultanov]

Spoiler

[olga_strubbe]

Thank you, @JoeM!  I loved the one tool solution - learned about '\b' RegEx expression.

[Amy_smart]

Here is my solution.