The challenge

Given two arrays, write a function to compute their intersection.

Example 1:

Input: nums1 = [1,2,2,1], nums2 = [2,2]
Output: [2,2]

Example 2:

Input: nums1 = [4,9,5], nums2 = [9,4,9,8,4]
Output: [4,9]

Note:

  • Each element in the result should appear as many times as it shows in both arrays.
  • The result can be in any order.

The solution in Python code

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def intersect(self, nums1: List[int], nums2: List[int]) -> List[int]:
    # create an `answer` list
    answer = []

    # loop through the first list
    for i in nums1:
        # check if the item is in the next list
        if i in nums2:
            # remove from the nums2 list
            nums2.remove(i)
            # add the answer to the `answer` list
            answer.append(i)

    # return our `answer` list
    return answer