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update 0404.左叶子之和: 修改 go 代码，优化 js 代码风格

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This commit is contained in:
Yuhao Ju
2022-12-03 00:41:43 +08:00
committed by GitHub
parent 89de738a18
commit e8978ea6a8
1 changed files with 42 additions and 41 deletions
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problems/0404.左叶子之和.md
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@ -35,7 +35,7 @@
![图二](https://code-thinking-1253855093.file.myqcloud.com/pics/20220902165805.png) ![图二](https://code-thinking-1253855093.file.myqcloud.com/pics/20220902165805.png)
相信通过这两个图，大家可以最左叶子的定义有明确理解了。 相信通过这两个图，大家对最左叶子的定义有明确理解了。
那么**判断当前节点是不是左叶子是无法判断的，必须要通过节点的父节点来判断其左孩子是不是左叶子。** 那么**判断当前节点是不是左叶子是无法判断的，必须要通过节点的父节点来判断其左孩子是不是左叶子。**
@ -298,48 +298,49 @@ class Solution:
```go ```go
func sumOfLeftLeaves(root *TreeNode) int { func sumOfLeftLeaves(root *TreeNode) int {
var res int if root == nil {
findLeft(root,&res) return 0
return res
} }
func findLeft(root *TreeNode,res *int){ leftValue := sumOfLeftLeaves(root.Left) // 左
//左节点
if root.Left != nil && root.Left.Left == nil && root.Left.Right == nil { if root.Left != nil && root.Left.Left == nil && root.Left.Right == nil {
*res=*res+root.Left.Val leftValue = root.Left.Val // 中
}
if root.Left!=nil{
findLeft(root.Left,res)
}
if root.Right!=nil{
findLeft(root.Right,res)
} }
rightValue := sumOfLeftLeaves(root.Right) // 右
return leftValue + rightValue
} }
``` ```
**迭代法** **迭代法(前序遍历)**
```go ```go
func sumOfLeftLeaves(root *TreeNode) int { func sumOfLeftLeaves(root *TreeNode) int {
var res int st := make([]*TreeNode, 0)
queue:=list.New() if root == nil {
queue.PushBack(root) return 0
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{ st = append(st, root)
queue.PushBack(node.Left) result := 0
for len(st) != 0 {
node := st[len(st)-1]
st = st[:len(st)-1]
if node.Left != nil && node.Left.Left == nil && node.Left.Right == nil {
result += node.Left.Val
} }
if node.Right != nil { if node.Right != nil {
queue.PushBack(node.Right) st = append(st, node.Right)
}
if node.Left != nil {
st = append(st, node.Left)
} }
} }
return result
} }
return res
}
``` ```