Behaviour of sting.match() [duplicate]

This question already has an answer here:

• Javascript Regex Match Capture is returning whole match, not group 2 answers

I am a little confused by the behaviour of the match method on javascripts string type.

I have a string containing:

<num> Number: 401 
<title> foreign minorities, Germany 

Now I want to parse 401 out of it using this regex:

/(Number: )(\d+)/g

This should give me two groups whereas the seconds should contain 401.

Trying this in node.js with this code:

const r_num = /Number: (\d+)/g;
let str = `<num> Number: 401 
    <title> foreign minorities, Germany `;
let res = str.match(r_num);

I am however only getting one element in my result array containing the full match rather then the two groups.

So how can I get groups rather then the full match in my result array?

via Jakob Abfalter