Skip to content
Branch: master
Find file History
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.
350. Intersection of Two Arrays II.go
350. Intersection of Two Arrays II_test.go

350. Intersection of Two Arrays II


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]


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

Follow up:

  • What if the given array is already sorted? How would you optimize your algorithm?
  • What if nums1's size is small compared to nums2's size? Which algorithm is better?
  • What if elements of nums2 are stored on disk, and the memory is limited such that you cannot load all elements into the memory at once?


这题是第 349 题的加强版。要求输出 2 个数组的交集元素,如果元素出现多次,要输出多次。


这一题还是延续第 349 题的思路。把数组一中的数字都放进字典中,另外字典的 key 是数组中的数字,value 是这个数字出现的次数。在扫描数组二的时候,每取出一个存在的数组,把字典中的 value 减一。如果 value 是 0 代表不存在这个数字。

You can’t perform that action at this time.