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.
给定两个数组,写一个函数来计算它们的交集。
例子:
给定 num1= [1, 2, 2, 1], nums2 = [2, 2], 返回 [2].
注意:
- 输出结果中每个元素出现的次数,应与元素在两个数组中出现的次数一致。
- 我们可以不考虑输出结果的顺序。
public class Solution {
public int[] intersection(int[] nums1, int[] nums2) {
TreeSet<Integer> set = new TreeSet<>();
for (int num : nums1)
set.add(num);
ArrayList<Integer> list = new ArrayList<>();
for (int num : nums2) {
if (set.contains(num)) {
list.add(num);
set.remove(num);
}
}
int[] res = new int[list.size()];
for (int i = 0; i < list.size(); i++)
res[i] = list.get(i);
return res;
}
}
测试代码
public class Test {
public static void main(String[] args) {
int[] a = { 1, 2, 2, 1 };
int[] b = { 2, 2 };
Solution solution = new Solution();
System.out.println(Arrays.toString(solution.intersection(a, b)));
}
}
运行结果