The idea is to write a function that takes two strings and returns a new string that repeats in the previous two: examples:
'ABBA' & 'AOHB' => 'AB' 'cohs' & 'ohba' => 'oh' A brute force solution would be nested for loops like so:
const x = 'ABCD' const y = 'AHOB' function subStr(str1, str2) { let final = '' for (let i = 0; i < str1.length; i++) { for (let j = 0; j < str2.length; j++) { if (str1[i] === str2[j]) { final += str1[i] } } } return final } console.log(subStr(x, y)) // => AB