Need help on Find Numbers with Regular Expressions

Need help on Find Numbers with Regular Expressions


Use the \d selector to select the number of numbers in the string, allowing for the possibility of one or more digit.

// Setup
var testString = “There are 3 cats but 4 dogs.”;

// Only change code below this line.

var expression = /.+/g; // Change this line

// Only change code above this line

// This code counts the matches of expression in testString
var digitCount = testString.match(expression).length;

I am not sure what to put in var expression = /.+/g; // Change this line.


Hello @crodier1 here is a nice little Interactive tutorial on Regular Expression that I found helpful.


Change var expression = /.+/g; to var expression = /\d+/g;

The . selects any character, the \d selects only digits and the + selects one or more of the elements matching the previous selector.

I suggest you take some time to learn basic Regex. Try RegexOne.


AWESOME! freeCodeCamp and CodeAcademy cover a lot of material in a very short amount of time. It’s great but it is also really nice having alternatives, like the link to RegexOne, to branch off into whatever subject may be covered in a single lesson. It’s all too easy to feel like I’m making progress by slamming through a bunch of lessons, but in reality I’m left with a shallow understanding of the concept and the versatility within. If you have any other resources/links like RegexOne I would love to know! Thank you!