findTheDifferenceOfTwoArrays.ts

/*
  Problem name: Find the Difference of Two Arrays

  Difficulty level: Easy

  Given two 0-indexed integer arrays nums1 and nums2, return a list answer of size 2 where:

  answer[0] is a list of all distinct integers in nums1 which are not present in nums2.
  answer[1] is a list of all distinct integers in nums2 which are not present in nums1.

  Note that the integers in the lists may be returned in any order.

  Examples: {
    Example 1: {
      Input: nums1 = [1,2,3], nums2 = [2,4,6]
      Output: [[1,3],[4,6]]
      Explanation:
      For nums1, nums1[1] = 2 is present at index 0 of nums2, whereas nums1[0] = 1 and nums1[2] = 3 are not present in nums2. Therefore, answer[0] = [1,3].
      For nums2, nums2[0] = 2 is present at index 1 of nums1, whereas nums2[1] = 4 and nums2[2] = 6 are not present in nums2. Therefore, answer[1] = [4,6].
    }

    Example 2: {
      Input: nums1 = [1,2,3,3], nums2 = [1,1,2,2]
      Output: [[3],[]]
      Explanation:
      For nums1, nums1[2] and nums1[3] are not present in nums2. Since nums1[2] == nums1[3], their value is only included once and answer[0] = [3].
      Every integer in nums2 is present in nums1. Therefore, answer[1] = [].
    }
  }
*/

function findDifference(nums1: number[], nums2: number[]): number[][] {
  const answer: number[][] = [[], []];

  const nums1Filter = [...new Set(nums1)];
  const nums2Filter = [...new Set(nums2)];

  nums1Filter.forEach((el) => {
    if (nums2Filter.indexOf(el) === -1) answer[0].push(el);
  });

  nums2Filter.forEach((el) => {
    if (nums1Filter.indexOf(el) === -1) answer[1].push(el);
  });

  return answer;
}

console.log(findDifference([1, 2, 3, 3], [1, 1, 2, 2]));