Jun 6, 2022 · May 16, 2022 · May 16, 2022 · May 16, 2022 · May 16, 2022 · May 16, 2022
diff --git a/problems/0203.移除链表元素.md b/problems/0203.移除链表元素.md
diff --git a/problems/0225.用队列实现栈.md b/problems/0225.用队列实现栈.md
diff --git a/problems/0232.用栈实现队列.md b/problems/0232.用栈实现队列.md
diff --git a/problems/剑指Offer58-II.左旋转字符串.md b/problems/剑指Offer58-II.左旋转字符串.md
Original file line number	Diff line number	Diff line change
Expand Up		@@ -266,6 +266,27 @@ public ListNode removeElements(ListNode head, int val) {
		}
		return head;
		}
	/**
	* 不添加虚拟节点and pre Node方式
	* 时间复杂度 O(n)
	* 空间复杂度 O(1)
	* @param head
	* @param val
	* @return
	*/
	public ListNode removeElements(ListNode head, int val) {
	while(head!=null && head.val==val){
	head = head.next;
	}
	ListNode curr = head;
	while(curr!=null){
	while(curr.next!=null && curr.next.val == val){
	curr.next = curr.next.next;
	}
	curr = curr.next;
	}
	return head;
	}
		```

		Python:
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -815,6 +815,89 @@ class MyStack {
		}
		}
		```
	Scala:

	使用两个队列模拟栈:
	```scala
	import scala.collection.mutable

	class MyStack() {

	val queue1 = new mutable.Queue[Int]()
	val queue2 = new mutable.Queue[Int]()

	def push(x: Int) {
	queue1.enqueue(x)
	}

	def pop(): Int = {
	var size = queue1.size
	// 将queue1中的每个元素都移动到queue2
	for (i <- 0 until size - 1) {
	queue2.enqueue(queue1.dequeue())
	}
	var res = queue1.dequeue()
	// 再将queue2中的每个元素都移动到queue1
	while (!queue2.isEmpty) {
	queue1.enqueue(queue2.dequeue())
	}
	res
	}

	def top(): Int = {
	var size = queue1.size
	for (i <- 0 until size - 1) {
	queue2.enqueue(queue1.dequeue())
	}
	var res = queue1.dequeue()
	while (!queue2.isEmpty) {
	queue1.enqueue(queue2.dequeue())
	}
	// 最终还需要把res送进queue1
	queue1.enqueue(res)
	res
	}

	def empty(): Boolean = {
	queue1.isEmpty
	}
	}
	```
	使用一个队列模拟:
	```scala
	import scala.collection.mutable

	class MyStack() {

	val queue = new mutable.Queue[Int]()

	def push(x: Int) {
	queue.enqueue(x)
	}

	def pop(): Int = {
	var size = queue.size
	for (i <- 0 until size - 1) {
	queue.enqueue(queue.head) // 把头添到队列最后
	queue.dequeue() // 再出队
	}
	queue.dequeue()
	}

	def top(): Int = {
	var size = queue.size
	var res = 0
	for (i <- 0 until size) {
	queue.enqueue(queue.head) // 把头添到队列最后
	res = queue.dequeue() // 再出队
	}
	res
	}

	def empty(): Boolean = {
	queue.isEmpty
	}
	}
	```
		-----------------------
		<div align="center"><img src=https://code-thinking.cdn.bcebos.com/pics/01二维码一.jpg width=500> </img></div>
Original file line number	Diff line number	Diff line change
Expand Up		@@ -495,6 +495,45 @@ void myQueueFree(MyQueue* obj) {
		obj->stackOutTop = 0;
		}
		```

	Scala:
	```scala
	class MyQueue() {
	import scala.collection.mutable
	val stackIn = mutable.Stack[Int]() // 负责出栈
	val stackOut = mutable.Stack[Int]() // 负责入栈

	// 添加元素
	def push(x: Int) {
	stackIn.push(x)
	}

	// 复用代码,如果stackOut为空就把stackIn的所有元素都压入StackOut
	def dumpStackIn(): Unit = {
	if (!stackOut.isEmpty) return
	while (!stackIn.isEmpty) {
	stackOut.push(stackIn.pop())
	}
	}

	// 弹出元素
	def pop(): Int = {
	dumpStackIn()
	stackOut.pop()
	}

	// 获取队头
	def peek(): Int = {
	dumpStackIn()
	val res: Int = stackOut.pop()
	stackOut.push(res)
	res
	}

	// 判断是否为空
	def empty(): Boolean = {
	stackIn.isEmpty && stackOut.isEmpty
	}
	}
	```
		-----------------------
		<div align="center"><img src=https://code-thinking.cdn.bcebos.com/pics/01二维码一.jpg width=500> </img></div>
Original file line number	Diff line number	Diff line change
Expand Up		@@ -290,6 +290,7 @@ func reverseString(_ s: inout [Character], startIndex: Int, endIndex: Int) {
		}
		```


		### PHP

		```php
Expand All		@@ -310,6 +311,9 @@ function reverse(&$s, $start, $end) {
		}
		```


	Scala:

		```scala
		object Solution {
		def reverseLeftWords(s: String, n: Int): String = {
Expand Down Expand Up		@@ -340,5 +344,6 @@ object Solution {




		-----------------------
		<div align="center"><img src=https://code-thinking.cdn.bcebos.com/pics/01二维码一.jpg width=500> </img></div>