题解 | #二叉树的后序遍历#

package main

import (
	. "nc_tools"

)

/*
 * type TreeNode struct {
 *   Val int
 *   Left *TreeNode
 *   Right *TreeNode
 * }
 */

/**
 * 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
 */
func postorderTraversal( root *TreeNode ) []int {
    // write code here
    if root == nil {
        return nil
    }
    var result []int
    var postorderTree  func (node *TreeNode)
    postorderTree = func(node *TreeNode) {
        if node == nil {
            return
        }
        postorderTree(node.Left)
        postorderTree(node.Right)
        result = append(result, node.Val)
    }
    postorderTree(root)
    return result
}