javascript - compare strings and get end difference

Question

I have two strings.
String A: "The quick brown fox"
String B: "The quick brown fox jumps over the lazy dog."

String B will always contain string A verbatim. There will never be a "quick black fox" or a "quick and speedy brown fox".

How do I get a "String C" of the difference "jumps over the lazy dog."?

Answer 1

const A = "The quick brown fox"

const B = "The quick brown fox jumps over the lazy dog."

const diff = (diffMe, diffBy) => diffMe.split(diffBy).join('')

const C = diff(B, A)

console.log(C) // jumps over the lazy dog.