Merge branch 'youngyangyang04:master' into master

This commit is contained in:
NevS
2021-06-14 00:11:55 +08:00
3 changed files with 226 additions and 0 deletions

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@ -486,6 +486,92 @@ class Solution:
Go
> 112. 路径总和
```go
//递归法
/**
* Definition for a binary tree node.
* type TreeNode struct {
* Val int
* Left *TreeNode
* Right *TreeNode
* }
*/
func hasPathSum(root *TreeNode, targetSum int) bool {
var flage bool //找没找到的标志
if root==nil{
return flage
}
pathSum(root,0,targetSum,&flage)
return flage
}
func pathSum(root *TreeNode, sum int,targetSum int,flage *bool){
sum+=root.Val
if root.Left==nil&&root.Right==nil&&sum==targetSum{
*flage=true
return
}
if root.Left!=nil&&!(*flage){//左节点不为空且还没找到
pathSum(root.Left,sum,targetSum,flage)
}
if root.Right!=nil&&!(*flage){//右节点不为空且没找到
pathSum(root.Right,sum,targetSum,flage)
}
}
```
> 113 递归法
```go
/**
* Definition for a binary tree node.
* type TreeNode struct {
* Val int
* Left *TreeNode
* Right *TreeNode
* }
*/
func pathSum(root *TreeNode, targetSum int) [][]int {
var result [][]int//最终结果
if root==nil{
return result
}
var sumNodes []int//经过路径的节点集合
hasPathSum(root,&sumNodes,targetSum,&result)
return result
}
func hasPathSum(root *TreeNode,sumNodes *[]int,targetSum int,result *[][]int){
*sumNodes=append(*sumNodes,root.Val)
if root.Left==nil&&root.Right==nil{//叶子节点
fmt.Println(*sumNodes)
var sum int
var number int
for k,v:=range *sumNodes{//求该路径节点的和
sum+=v
number=k
}
tempNodes:=make([]int,number+1)//新的nodes接受指针里的值防止最终指针里的值发生变动导致最后的结果都是最后一个sumNodes的值
for k,v:=range *sumNodes{
tempNodes[k]=v
}
if sum==targetSum{
*result=append(*result,tempNodes)
}
}
if root.Left!=nil{
hasPathSum(root.Left,sumNodes,targetSum,result)
*sumNodes=(*sumNodes)[:len(*sumNodes)-1]//回溯
}
if root.Right!=nil{
hasPathSum(root.Right,sumNodes,targetSum,result)
*sumNodes=(*sumNodes)[:len(*sumNodes)-1]//回溯
}
}
```
JavaScript
0112.路径总和

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@ -226,6 +226,71 @@ class Solution:
```
Go
> 递归法
```go
/**
* Definition for a binary tree node.
* type TreeNode struct {
* Val int
* Left *TreeNode
* Right *TreeNode
* }
*/
func sumOfLeftLeaves(root *TreeNode) int {
var res int
findLeft(root,&res)
return res
}
func findLeft(root *TreeNode,res *int){
//左节点
if root.Left!=nil&&root.Left.Left==nil&&root.Left.Right==nil{
*res=*res+root.Left.Val
}
if root.Left!=nil{
findLeft(root.Left,res)
}
if root.Right!=nil{
findLeft(root.Right,res)
}
}
```
> 迭代法
```go
/**
* Definition for a binary tree node.
* type TreeNode struct {
* Val int
* Left *TreeNode
* Right *TreeNode
* }
*/
func sumOfLeftLeaves(root *TreeNode) int {
var res int
queue:=list.New()
queue.PushBack(root)
for queue.Len()>0{
length:=queue.Len()
for i:=0;i<length;i++{
node:=queue.Remove(queue.Front()).(*TreeNode)
if node.Left!=nil&&node.Left.Left==nil&&node.Left.Right==nil{
res=res+node.Left.Val
}
if node.Left!=nil{
queue.PushBack(node.Left)
}
if node.Right!=nil{
queue.PushBack(node.Right)
}
}
}
return res
}
```
JavaScript:
递归版本
```javascript
@ -275,6 +340,7 @@ var sumOfLeftLeaves = function(root) {
-----------------------
* 作者微信:[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw)
* B站视频[代码随想录](https://space.bilibili.com/525438321)

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@ -298,6 +298,80 @@ class Solution:
```
Go
> 递归法
```go
/**
* Definition for a binary tree node.
* type TreeNode struct {
* Val int
* Left *TreeNode
* Right *TreeNode
* }
*/
var maxDeep int // 全局变量 深度
var value int //全局变量 最终值
func findBottomLeftValue(root *TreeNode) int {
if root.Left==nil&&root.Right==nil{//需要提前判断一下不要这个if的话提交结果会出错但执行代码不会。防止这种情况出现故先判断是否只有一个节点
return root.Val
}
findLeftValue (root,maxDeep)
return value
}
func findLeftValue (root *TreeNode,deep int){
//最左边的值在左边
if root.Left==nil&&root.Right==nil{
if deep>maxDeep{
value=root.Val
maxDeep=deep
}
}
//递归
if root.Left!=nil{
deep++
findLeftValue(root.Left,deep)
deep--//回溯
}
if root.Right!=nil{
deep++
findLeftValue(root.Right,deep)
deep--//回溯
}
}
```
> 迭代法
```go
/**
* Definition for a binary tree node.
* type TreeNode struct {
* Val int
* Left *TreeNode
* Right *TreeNode
* }
*/
func findBottomLeftValue(root *TreeNode) int {
queue:=list.New()
var gradation int
queue.PushBack(root)
for queue.Len()>0{
length:=queue.Len()
for i:=0;i<length;i++{
node:=queue.Remove(queue.Front()).(*TreeNode)
if i==0{gradation=node.Val}
if node.Left!=nil{
queue.PushBack(node.Left)
}
if node.Right!=nil{
queue.PushBack(node.Right)
}
}
}
return gradation
}
```
JavaScript:
1. 递归版本
```javascript