Reuse patterns using capture

Tell us what’s happening:
I dont really understand why this does not work. To me, it checks out. Anyone can help?
Your code so far

let repeatNum = "42 42 42";
let reRegex = /(\d+)(\s)\1\2\1$/; // Change this line
let result = reRegex.test(repeatNum);

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/89.0.4389.114 Safari/537.36.

Challenge: Reuse Patterns Using Capture Groups

Link to the challenge:

You are almost there and the main logic is good. but without a ^ at the beginning of your regex this can match the last three numbers of any repeating series of the same number. Such as: 2 2 2 2 would find a match in the last three 2s.

EDIT: i use this website extensively when building regex from scratch. the visualization and resources are super helpful:

1 Like

I just had an Aha moment. Thank you! and thanks for the link as well.