2215-find-the-difference-of-two-arrays.rb

# frozen_string_literal: true

# 2215. Find the Difference of Two Arrays
# https://leetcode.com/problems/find-the-difference-of-two-arrays
# Easy

=begin
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.

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] = [].

Constraints:
* 1 <= nums1.length, nums2.length <= 1000
* -1000 <= nums1[i], nums2[i] <= 1000
=end

# @param {Integer[]} nums1
# @param {Integer[]} nums2
# @return {Integer[][]}
def find_difference(*arrays)
  arrays.permutation.map { _1.reduce(:-).uniq }
end

# **************** #
#       TEST       #
# **************** #

require "test/unit"
class Test_find_difference < Test::Unit::TestCase
  def test_
    assert_equal [[1, 3], [4, 6]], find_difference([1, 2, 3], [2, 4, 6])
    assert_equal [[3], []], find_difference([1, 2, 3, 3], [1, 1, 2, 2])
  end
end