Regular expressions Capture Groups help to understand

[john-98]

can someone help me to understand how \1\1 works here?

let repeatRegex = /(\w+) \1 \1/;   <-------- how this works ?
repeatRegex.test(repeatStr); 
repeatStr.match(repeatRegex); 

Link to the challenge:

freeCodeCamp.org

[ghulamshabirbaloch]

@john-98

(\w+)

the parentheses in regular expression define a capture group, expression in the parentheses match characters and you can capture the matched characters by numbers starting from 1 preceding them by backslash. if there had been two capture groups e.g. /(\w+)(\d+)/ then you can access the first one by \1, and second one by \2. you can learn and practice regex online at regexr.com