349.TwoArrayIntesection

问题

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

Example 1:

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

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

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

解决方案

class Solution {
    public int[] intersection(int[] nums1, int[] nums2) {
 	   	Set<Integer> set1 = new HashSet();
		Set<Integer> set2 = new HashSet();
		for (int i = 0; i < nums1.length; i++) {
			set1.add(nums1[i]);
		}
		
		for (int j = 0; j < nums2.length; j++) {
			if (set1.contains(nums2[j])) {
				set2.add(nums2[j]);
			}
		}
		int[] num = new int[set2.size()];
		int i = 0;
		for (Integer n : set2) {
			num[i] = n;
			i++;
		}
		
		return num;
	}
}