LeetCode | 广度优先遍历

[
     [1],
     [3,2,4],
     [5,6]
]

for child in current.children:    
                    que.append(child);

# 运行效率：90.36%
"""
# Definition for a Node.
class Node(object):
    def __init__(self, val, children):
        self.val = val
        self.children = children
"""
class Solution(object):

    def levelOrder(self, root):
        """
        :type root: Node
        :rtype: List[List[int]]
        """
        if not root:
            return [];
        que = [];    
        res = [];    
        que.append(root);    
        while len(que):     
            l = len(que);
            sub = [];        
            for i in range(l):
                current = que.pop(0);    
                sub.append(current.val);
                for child in current.children:    
                    que.append(child);
            res.append(sub);    
        return res;

    3
   / \
  9  20
    /  \
   15   7

[
  [3],
  [9,20],
  [15,7]
]

# 运行效率：99.76%
# Definition for a binary tree node.
# class TreeNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None

class Solution(object):
    def levelOrder(self, root):
        if not root:
            return []
        ret = []
        ret.append(root)
        ret2 = []
        while len(ret) != 0:
            temp = []
            length = len(ret)
            for index in range(length):
                tempValue = ret.pop(0)
                temp.append(tempValue.val)
                if tempValue.left is not None:
                    ret.append(tempValue.left)
                if tempValue.right is not None:
                    ret.append(tempValue.right)
            ret2.append(temp)
        return ret2