Kth Distinct String in an Array

export function kthDistinct(arr: string[], k: number): string {
  const answer = new Set<string>();
 
  const set = new Set<string>();
  arr.forEach((num) => {
    if (!set.has(num)) {
      answer.add(num);
      set.add(num);
    } else {
      answer.delete(num);
    }
  });
 
  return k <= answer.size ? [...answer][k - 1] : '';
}