递归
import java.util.*;
/*
* public class TreeNode {
* int val = 0;
* TreeNode left = null;
* TreeNode right = null;
* public TreeNode(int val) {
* this.val = val;
* }
* }
*/
public class Solution {
public void inorder(ArrayList<Integer> list,TreeNode root){
if(root==null){
return ;
}
inorder(list,root.left);
list.add(root.val);
inorder(list,root.right);
}
/**
* 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可
*
*
* @param root TreeNode类
* @return int整型一维数组
*/
public int[] inorderTraversal (TreeNode root) {
// write code here
ArrayList<Integer> list=new ArrayList<>();
inorder(list,root);
int[] res=new int[list.size()];
res=list.stream().mapToInt(Integer::valueOf).toArray();//ArrayList转化为int[]
return res;
}
}

京公网安备 11010502036488号