最近做的题记录下. 258. Add Digits Given a non-negative integer num, repeatedly add all its digits until the result has only one digit. For example: Given num = 38, the process is like: 3 + 8 = 11, 1 + 1 = 2. Since 2 has only one digit, return it. int addDigi…

258. Add Digits Digit root 数根问题 /** * @param {number} num * @return {number} */ var addDigits = function(num) { var b = (num-1) % 9 + 1 ; return b; }; //之所以num要-1再+1;是因为特殊情况下:当num是9的倍数时,0+9的数字根和0的数字根不同. 性质说明 1.任何数加9的数字根还是它本身.(特殊情况num=0)        小学学加法的…

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…

Question 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. Solution 1 -- Recursion Recursion way is easy to think. Similar with "Minimum Dep…

题目: 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. 题解: 递归解法:                                                            } 非递归解法,参考codegan…

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 给定一个二叉树,找出他的最小的深度. 最小的深度,指的是从根节点到叶子节点的,经历的最多的节点个数. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Given a binary tree, find its max…

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. Hide Tags Tree Depth-first Search     简单的深度搜索 #include <iostream> using namespace std; /*…

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…

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. Hide Tags Tree Depth-first Search /** * Definition for binary tree * struct TreeNode { * i…

Problem: 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. 初看本题第一印象为递归写法.首先找出终止条件:node == NULL.若未进入递归终止状态,则分左子树和又子树进行递归,最终返回累加最大的值.其代码如下: /*…