lintcode:二叉樹的層次遍歷
方法一：二叉樹的層序遍歷，需要借助兩個佇列空間。
"""
definition of treenode:
class treenode:
def __init__(self, val):
self.val = val
self.left, self.right = none, none
""""""
definition of treenode:
class treenode:
def __init__(self, val):
self.val = val
self.left, self.right = none, none
"""class
solution:
""" @param root: the root of binary tree.
@return: level order in a list of lists of integers
"""deflevelorder
(self, root):
# write your code here
if root == none:
return
l1 =
l2 =
if root.left != none:
if root.right != none:
m = 1
while(len(l2) != 0):
n = len(l2)
for i in range(n):
if l2[0].left != none:
if l2[0].right != none:
l2.remove(l2[0])
m += 1
return l1
題目要求只用乙個佇列實現，可以考慮把l2放在l1的某個位置，最後再刪除就可以了。
"""
definition of treenode:
class treenode:
def __init__(self, val):
self.val = val
self.left, self.right = none, none
"""class
solution:
""" @param root: the root of binary tree.
@return: level order in a list of lists of integers
"""deflevelorder
(self, root):
# write your code here
if root == none:
return
l1 =
if root.left != none:
if root.right != none:
m = 2
while(len(l1[1]) != 0):
n = len(l1[1])
for i in range(n):
if l1[1][0].left != none:
if l1[1][0].right != none:
l1[1].remove(l1[1][0])
m += 1
l1.remove(l1[1])
return l1
/**
* definition of treenode:
* public class treenode
* }*/public
class solution
linkedlist> l = new linkedlist>();
l.add(new linkedlist());
l.get(0).add(root);
l.add(new linkedlist());
if(root.left != null)
if(root.right != null)
int m = 2;
while(l.get(1).size() != 0)
if(l.get(1).get(0).right != null)
l.get(m).add(l.get(1).get(0));
l.get(1).remove(l.get(1).get(0));
}m += 1;
}arraylist> ans = new arraylist>();
for(int i=0; inew arraylist());
for(int j=0; jget(i).size(); j++)
}ans.remove(1);
return ans;
}}
二叉樹層次遍歷 LintCode
給出一棵二叉樹，返回其節點值的層次遍歷 逐層從左往右訪問 給一棵二叉樹 遍歷結果 3 9,20 15,7 主要思想 為了層次遍歷，就要一層一層地處理資料。先將根節點入隊，之後搜尋其左子樹與右子樹，若非空，則入隊，並將根節點出隊。按照此方法，依此處理。ifndef c69 h define c69 h...
lintcode 二叉樹的層次遍歷
給出一棵二叉樹，返回其節點值從底向上的層次序遍歷 按從葉節點所在層到根節點所在的層遍歷，然後逐層從左往右遍歷 您在真實的面試中是否遇到過這個題？yes 樣例給出一棵二叉樹,3 9 20 15 7按照從下往上的層次遍歷為 15,7 9,20 3 definition of treenode publi...
Lintcode 二叉樹的層次遍歷
給出一棵二叉樹，返回其節點值的層次遍歷 逐層從左往右訪問 樣例 1 輸入 輸出 1 2,3 解釋 1 2 3 它將被序列化為 層次遍歷樣例 2 輸入 輸出 1 2 3 解釋 1 2 3 它將被序列化為 層次遍歷python definition of treenode class treenode ...