2017/3/23 15:41:47

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.

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作弊版：Python

class Solution(object):    def intersection(self, nums1, nums2):        return list(set( nums1 ) & set(nums2))

 

版本1：Java  O(m*n)  循环检查  

public class Solution {    public int[] intersection(int[] nums1, int[] nums2) {        Set
       
         set = new HashSet
        
         ();        for ( int i=0;i
        
       

 

版本2：Java  O(m+n)  借助哈希表+Set，或者双Set

public int[] intersection(int[] nums1, int[] nums2) {		Map
      
        map = new Hashtable
       
        ();		Set
        
          set = new TreeSet
         
          ();        for ( int i=0;i