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Merge branch 'youngyangyang04:master' into master

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`@@ -352,6 +352,38 @@ class Solution:`
`352`	`352`	`return mid_root`
`353`	`353`	```
`354`	`354`
	`355`	`+迭代(左闭右开)`
	`356`	+```python
	`357`	`+class Solution:`
	`358`	`+ def sortedArrayToBST(self, nums: List[int]) -> Optional[TreeNode]:`
	`359`	`+ if len(nums) == 0: return None`
	`360`	`+ root = TreeNode() # 初始化`
	`361`	`+ nodeSt = [root]`
	`362`	`+ leftSt = [0]`
	`363`	`+ rightSt = [len(nums)]`
	`364`	`+`
	`365`	`+ while nodeSt:`
	`366`	`+ node = nodeSt.pop() # 处理根节点`
	`367`	`+ left = leftSt.pop()`
	`368`	`+ right = rightSt.pop()`
	`369`	`+ mid = left + (right - left) // 2`
	`370`	`+ node.val = nums[mid]`
	`371`	`+`
	`372`	`+ if left < mid: # 处理左区间`
	`373`	`+ node.left = TreeNode()`
	`374`	`+ nodeSt.append(node.left)`
	`375`	`+ leftSt.append(left)`
	`376`	`+ rightSt.append(mid)`
	`377`	`+`
	`378`	`+ if right > mid + 1: # 处理右区间`
	`379`	`+ node.right = TreeNode()`
	`380`	`+ nodeSt.append(node.right)`
	`381`	`+ leftSt.append(mid + 1)`
	`382`	`+ rightSt.append(right)`
	`383`	`+`
	`384`	`+ return root`
	`385`	+```
	`386`	`+`
`355`	`387`	`## Go`
`356`	`388`
`357`	`389`	`递归(隐含回溯)`

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`@@ -348,6 +348,24 @@ class Solution:`
`348`	`348`	`return root`
`349`	`349`	```
`350`	`350`
	`351`	`+普通二叉树的删除方式`
	`352`	+```python
	`353`	`+class Solution:`
	`354`	`+ def deleteNode(self, root: Optional[TreeNode], key: int) -> Optional[TreeNode]:`
	`355`	`+ if not root: return root`
	`356`	`+ if root.val == key:`
	`357`	`+ if not root.right: # 这里第二次操作目标值:最终删除的作用`
	`358`	`+ return root.left`
	`359`	`+ tmp = root.right`
	`360`	`+ while tmp.left:`
	`361`	`+ tmp = tmp.left`
	`362`	`+ root.val, tmp.val = tmp.val, root.val # 这里第一次操作目标值:交换目标值其右子树最左面节点。`
	`363`	`+`
	`364`	`+ root.left = self.deleteNode(root.left, key)`
	`365`	`+ root.right = self.deleteNode(root.right, key)`
	`366`	`+ return root`
	`367`	+```
	`368`	`+`
`351`	`369`	`迭代法`
`352`	`370`	```python
`353`	`371`	`class Solution:`

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`@@ -299,6 +299,32 @@ class Solution:`
`299`	`299`	`return root`
`300`	`300`	```
`301`	`301`
	`302`	`+迭代`
	`303`	+```python
	`304`	`+class Solution:`
	`305`	`+ def trimBST(self, root: Optional[TreeNode], low: int, high: int) -> Optional[TreeNode]:`
	`306`	`+ if not root: return root`
	`307`	`+ # 处理头结点,让root移动到[L, R] 范围内,注意是左闭右开`
	`308`	`+ while root and (root.val < low or root.val > high):`
	`309`	`+ if root.val < low: # 小于L往右走`
	`310`	`+ root = root.right`
	`311`	`+ else: # 大于R往左走`
	`312`	`+ root = root.left`
	`313`	`+ # 此时root已经在[L, R] 范围内,处理左孩子元素小于L的情况`
	`314`	`+ cur = root`
	`315`	`+ while cur:`
	`316`	`+ while cur.left and cur.left.val < low:`
	`317`	`+ cur.left = cur.left.right`
	`318`	`+ cur = cur.left`
	`319`	`+ # 此时root已经在[L, R] 范围内,处理右孩子大于R的情况`
	`320`	`+ cur = root`
	`321`	`+ while cur:`
	`322`	`+ while cur.right and cur.right.val > high:`
	`323`	`+ cur.right = cur.right.left`
	`324`	`+ cur = cur.right`
	`325`	`+ return root`
	`326`	+```
	`327`	`+`
`302`	`328`	`## Go`
`303`	`329`
`304`	`330`	```go

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