[leetcode] 5. Minimum Depth of Binary Tree】的更多相关文章

[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…
[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…
    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 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…
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…
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…
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. 题目标题:Tree 这道题目给了我们一个二叉树,让我们找到它最小的深度,注意这里的最小深度是指root 到一个 leaf node. 举个例子: 1 /   2 / 3 这种情况,…
problem 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. problem analysis: 第一步,设计演算法:遍历一棵树的方法有两种,BFS and DFS,思考了下,BFS是一圈一圈的扩张出…
题目简述: 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. 解题思路: # Definition for a binary tree node # class TreeNode: # def __init__(self, x):…
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. 简单题,不过注意叶子结点是两个子树都是NULL的指针.只有一个子树NULL的不是. struct TreeNode { int val; TreeNode *left; TreeN…
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.  求树的最低高度. 没什么技巧性,用队列,遇到叶子结点的时候返回结果.   /** * Definition for a binary tree node. * public cl…
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. 解题思路: 递归. 代码描述: /** * Definition for a binary tree node. * public class TreeNode { *…
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. 思路: 题意是求一颗二叉树的的最短路径 思路可以参考求二叉树的深度的算法,还是用递归的思想,考虑上级节点和下级左右子树的关系 代码: /** * Definition fo…
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…
二叉树基本功练习题,题目如下: 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. 就是找最短的那条从根到叶,跟上一道题一样直接那递归上就行.解法如下: /** * Definition for binary tree * stru…
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. 题意很清楚,找到二叉树中深度最短的一条路径,DFS(貌似是面试宝典上的一道题) 类似的一道题:http://www.cnblogs.com/double-win/p/3737262…
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…
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. 解题思路:注意minimum depth最后遍历的那个点,left right都必须为null,JAVA实现如下: public int minDepth(TreeNode roo…
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. 题解:注意没有的分支不算. /** * Definition for a binary tree node. * struct TreeNode { * int val; * Tr…
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. 题意: 给定一棵二叉树.返回它的最小高度. 最小高度是指从根节点到近期的叶子节点的最短路径中的节点的数目. 算法分析: * 借助堆 * 类似<Binary Tree Lev…
/** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */ class Solution { public int minDepth(TreeNode root) { if(root == null){ return 0; } if((root.left =…
http://oj.leetcode.com/problems/minimum-depth-of-binary-tree/ 贡献了一次runtime error,因为如果输入为{}即空的时候,出现了crash.其实这种情况也处理了,但是顺序不对,如下: if(root->left == NULL && root->right == NULL) return 1; if(root==NULL ) return 0;如果输入是空的话,会对空->left访问left,但这是错误…
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…
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 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. 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…
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),…
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…
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…