题解 | #按之字形顺序打印二叉树#

package main

// import "fmt"
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 pRoot TreeNode类
 * @return int整型二维数组
 */
func Print(pRoot *TreeNode) [][]int {
	// write code here
	// write code here
	res := [][]int{}
	struck := []*TreeNode{}
	struck = append(struck, pRoot)
	start := 0
	p := pRoot
	// res = append(res, []int{root.Val})
	for k := 1; p != nil; k++ {
		lin := []int{}
		le := len(struck)
		for i := start; i < le; i++ {
			lin = append(lin, struck[i].Val)
			start++

			if struck[i].Left != nil {
				struck = append(struck, struck[i].Left)
			}
			if struck[i].Right != nil {
				struck = append(struck, struck[i].Right)
			}

		}
		if len(lin) == 0 {
			break
		} else {
			if k%2 == 0 {
				length := len(lin)
				for i := 0; i < length/2; i++ {
					temp := lin[length-1-i]
					lin[length-1-i] = lin[i]
					lin[i] = temp
				}
			}
			res = append(res, lin)
		}

	}
	return res
}