349. Intersection of Two Arrays

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

Example:
Given nums1 = [1, 2, 2, 1], nums2 = [2, 2], return [2].

Note:

• Each element in the result must be unique.
• The result can be in any order.

class Solution(object):    def intersection(self, nums1, nums2):        """        :type nums1: List[int]        :type nums2: List[int]        :rtype: List[int]        """        small = []        big = []        if len(nums1) < len(nums2):            small = nums1            big = nums2        else:            small = nums2            big = nums1        r = []        for i in small:            if i in big and i not in r:                r.append(i)        return r

虽然AC了，但是用时太长了，需要优化一下
优化的思路是使用set，去重

class Solution(object):    def intersection(self, nums1, nums2):        """        :type nums1: List[int]        :type nums2: List[int]        :rtype: List[int]        """        s = set(nums2)# 去重        b = set(nums1)        r = []        for i in s:            if i in b and i not in r:                r.append(i)                b.remove(i)            return r