LeetCode 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].

 

思路：

利用ArrayList的contains(Object o)方法进行交集的查询。

 

解法：

import java.util.ArrayList;

public class Solution
{
    public int[] intersection(int[] nums1, int[] nums2)
    {
        ArrayList<Integer> list1 = new ArrayList<>();
        ArrayList<Integer> list2 = new ArrayList<>();
        ArrayList<Integer> list = new ArrayList<>();

        for(int i = 0; i < nums1.length; i++)
            list1.add(nums1[i]);
        for(int i = 0; i < nums2.length; i++)
            list2.add(nums2[i]);

        for(int i = 0; i < nums1.length; i++)
        {
            if(list2.contains(list1.get(i)) && !(list.contains(list1.get(i))))
                list.add(list1.get(i))
        }

        int[] array = new int[list.size()];
        for(int i = 0; i < array.length; i++)
            array[i] = list.get(i);    

        return array;
    }
}