[Leetcode] Maximum and Minimum Depth of Binary Tree 二叉树的最小最大深度 (最小有3种解法) 描述 解析 递归深度优先搜索 当求最大深度时,我们只要在左右子树中取较大的就行了. 然而最小深度时,如果左右子树中有一个为空会返回0,这时我们是不能算做有效深度的. 所以分成了三种情况,左子树为空,右子树为空,左右子树都不为空.当然,如果左右子树都为空的话,就会返回1. 广度优先搜索(类似层序遍历的思想) 递归解法本质是深度优先搜索,但因为我们是求最小…
[LeetCode]Minimum Depth of Binary Tree Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 递归和非递归,此提比较简单.广度优先遍历即可.关键之处就在于如何保持访问深度. 下面是4种代码: im…
Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 给一个二叉树,找出它的最小深度.最小深度是从根节点向下到最近的叶节点的最短路径,就是最短路径的节点个数. 解法1:DFS 解法2: BFS Java: DFS, Time Comp…
Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 二叉树的经典问题之最小深度问题就是就最短路径的节点个数,还是用深度优先搜索DFS来完成,万能的递归啊...请看代码: /** * Definition for binary tre…
Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 方法一: 层次遍历.主体的思想不变,程序的主体结构也不变,具体遍历过程参照二叉树的层次遍历.关键在于终止条件,在某一层中,节点遍历的顺序是从左往右的,若是最短路径出现在该层中,则其…
给定一个二叉树,找出其最小深度.最小深度是从根节点到最近叶节点的最短路径的节点数量.详见:https://leetcode.com/problems/minimum-depth-of-binary-tree/description/ Java实现: 递归实现: /** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * Tree…
要求:此题正好和Maximum Depth of Binary Tree一题是相反的,即寻找二叉树的最小的深度值:从根节点到最近的叶子节点的距离. 结题思路:和找最大距离不同之处在于:找最小距离要注意(l<r)? l+1:r+1的区别应用,因为可能存在左右子树为空的情况,此时值就为0,但显然值是不为0的(只有当二叉树为空才为0),所以,在这里注意一下即可! 代码如下: struct TreeNode { int val; TreeNode *left; TreeNode *right; Tree…
Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. Hide Tags Tree Depth-first Search       这题是找二叉树的最小深度,这是广度搜索比较好吧,为啥提示给的是 深度优先呢. 判断树是否为空 将ro…
找出最短的从叶子到根的路径长 可以回忆Maximum Depth of Binary Tree的写法,只不过在!root,我把它改成了10000000,还有max函数改成了min函数,最后的值如果是10000000,毫无疑问这棵树肯定为空,因此在最后有(d>=1000000)?0:d; /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *righ…
题目描述: Given a binary tree, find its minimum depth.The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 特殊输入: 只有两个节点时,树的深度是2.但是如果只考虑左子树或右子树为空.结果会返回1. 两个错误的代码:(不应该以子树空判断结束) 实现1:该代码是错误的class…
LeetCode:Minimum Depth of Binary Tree Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 算法1:dfs递归的求解 class Solution { public: int minDepth(T…
    题目URL:https://leetcode.com/problems/minimum-depth-of-binary-tree/ 111. Minimum Depth of Binary Tree My Submissions Question Total Accepted: 94580 Total Submissions: 312802 Difficulty: Easy Given a binary tree, find its minimum depth. The minimum…
Given a binary tree, find its maximum depth. The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node. 求二叉树的最大深度问题用到深度优先搜索DFS,递归的完美应用,跟求二叉树的最小深度问题原理相同.代码如下: C++ 解法一: class Solution { public: in…
Minimum Depth of Binary Tree Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 比较左子树和右子树的深度,取小的那个返回上来,并+1. 需要注意的是如果没有左子树或右子树.那么无条件取存在的那一边子树深…
Minimum Depth of Binary Tree Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 和上一题对应,求二叉树的最小深度. 解题思路: 参考上一题Maximun Depth of Binary Tree中最后那…
Minimum Depth of Binary Tree Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. SOLUTION 1: 递归 这种递归解法更简单.因为在本层递归中不需要考虑左右子树是否为NULL的情况.因为我们直接把…
1.  Path Sum Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. For example: Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \ 7…
Given a binary tree, find its maximum depth. The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node. Note: A leaf is a node with no children. Example: Given binary tree [3,9,20,null,null,15,7…
Minimum Depth of Binary Tree OJ: https://oj.leetcode.com/problems/minimum-depth-of-binary-tree/ Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf…
Minimum Depth of Binary Tree Total Accepted: 24760 Total Submissions: 83665My Submissions Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node.…
Minimum Depth of Binary Tree Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 与Maximum Depth of Binary Tree对照看 解法一:深度优先遍历 借助栈进行深度优先遍历(DFS),…
111. Minimum Depth of Binary Tree Easy Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. Note: A leaf is a node with no children. Example: G…
Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. Note: A leaf is a node with no children. Example: Given binary tree [3,9,20,null,null,15,7…
Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. Note: A leaf is a node with no children. Example: Given binary tree [3,9,20,null,null,15,7…
Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 求二叉树的最小深度,额,简单的递归而已,代码如下: class Solution { public: int minDepth(TreeNode* root) { ; int le…
求二叉树的最小深度: /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { public: int minDepth(TreeNode* root) { ; int l = m…
Description Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. Example Given a binary tree as follow: 1 / \ 2 3 / \ 4 5 The minimum depth is …
题目 Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 分析 求二叉树的最小深度:根节点到最近叶子节点的路径长度. 同样采用递归的思想: 当根节点为空,返回0: 当根节点为唯一的二叉树节点时,返回1: 否则,求解并返回 最小(非空…
Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. Hide Tags Tree Depth-first Search  最小深度的意思是从根节点到最近叶节点的最短路径!不是说遇到只有一个孩子的节点就返回. 所以递归的返回条件要分四…
Given a binary tree, find its maximum depth. The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node. Have you met this question in a real interview? Yes Example Given a binary tree as follow:…