Discussion on: A coding interview question asked at Google

[rascanoo]

Using Regex:

const check = arr => {
  let regex = /[a-z]-B/g

  let [x, y] = arr.map(elm => {
    elm = elm.replace(/,/g, '');

    while (regex.test(elm)) {
      elm = elm.replace(regex, '');
    }

    return elm.replace(/-B/g, '');
  });

  return x === y;
}

console.log(check(["a,b,c,d", "a,b,c,c,-B,d"])); // true
console.log(check(["-B,-B,-B,c,c", "c,c"])); // true
console.log(check(["", "a,-B,-B,a,-B,a,b,c,c,c,d"])); // false
console.log(check(["a,a,a,-B,-B,c", "a,c"])); //true

[DownloadPizza]

This is actually awesome, it shouldn't take long to make this into something that works with multiple lines

[Simon Landry]

I'm not convinced this works with every case; You're missing some edge cases such as

['a,a,a,-B,-B,c', 'a,c']

[rascanoo]

Hi Simon,

You are correct, well spotted. I changed the solution to reflect your case and hopefully all cases :-)
Couldn't do it with one regex though :-(