算法题 Level Order Traversal of Binary Tree

Hi, here's your problem today. This problem was recently asked by Microsoft:

Given the root of a binary tree, print its level-order traversal. For example:

  1

 / \

2   3

   / \

  4   5

The following tree should output 1, 2, 3, 4, 5.

class Node:

  def __init__(self, val, left=None, right=None):

    self.val = val

    self.left = left

    self.right = right



def print_level_order(root):

  # Fill this in.



root = Node(1, Node(2), Node(3, Node(4), Node(5)))

print_level_order(root)

# 1 2 3 4 5