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feat: add python and java solutions to leetcode problem: No.0225
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‎.github/workflows/prettier.yml

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uses: creyD/prettier_action@v3.0
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with:
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prettier_options: --write **/*.{js,c,cpp,go,rb,java,cs,py,scala,md}
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commit_message: 'docs: prettify code'
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commit_message: 'style: prettify code'
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env:
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GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

‎README.md

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### 栈和队列
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1. [有效的括号](/solution/0000-0099/0020.Valid%20Parentheses/README.md)
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1. [用栈实现队列](/solution/0200-0299/0232.Implement%20Queue%20using%20Stacks/README.md)
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1. [用队列实现栈](/solution/0200-0299/0225.Implement%20Stack%20using%20Queues/README.md)
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### 动态规划
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### 混合问题

‎README_EN.md

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@@ -71,6 +71,10 @@ Complete solutions to [LeetCode](https://leetcode-cn.com/problemset/all/), [LCOF
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### Stack & Queue
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1. [Valid Parentheses](/solution/0000-0099/0020.Valid%20Parentheses/README_EN.md)
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1. [Implement Queue using Stacks](/solution/0200-0299/0232.Implement%20Queue%20using%20Stacks/README_EN.md)
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1. [Implement Stack using Queues](/solution/0200-0299/0225.Implement%20Stack%20using%20Queues/README_EN.md)
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### Dynamic Programming
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### Misc

‎solution/0200-0299/0225.Implement Stack using Queues/README.md

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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```python
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class MyStack:
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def __init__(self):
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"""
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Initialize your data structure here.
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"""
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self.q = []
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def push(self, x: int) -> None:
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"""
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Push element x onto stack.
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"""
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self.q.append(x)
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n = len(self.q)
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for i in range(1, n):
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self.q.append(self.q.pop(0))
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def pop(self) -> int:
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"""
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Removes the element on top of the stack and returns that element.
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"""
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return self.q.pop(0)
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def top(self) -> int:
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"""
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Get the top element.
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"""
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return self.q[0]
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def empty(self) -> bool:
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"""
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Returns whether the stack is empty.
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"""
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return len(self.q) == 0
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# Your MyStack object will be instantiated and called as such:
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# obj = MyStack()
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# obj.push(x)
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# param_2 = obj.pop()
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# param_3 = obj.top()
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# param_4 = obj.empty()
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```
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### **Java**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```java
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class MyStack {
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private Deque<Integer> q;
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/** Initialize your data structure here. */
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public MyStack() {
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q = new ArrayDeque<>();
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}
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/** Push element x onto stack. */
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public void push(int x) {
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q.offerLast(x);
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int n = q.size();
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while (n-- > 1) {
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q.offerLast(q.pollFirst());
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}
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}
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/** Removes the element on top of the stack and returns that element. */
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public int pop() {
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return q.pollFirst();
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}
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/** Get the top element. */
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public int top() {
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return q.peekFirst();
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}
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/** Returns whether the stack is empty. */
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public boolean empty() {
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return q.isEmpty();
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}
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}
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/**
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* Your MyStack object will be instantiated and called as such:
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* MyStack obj = new MyStack();
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* obj.push(x);
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* int param_2 = obj.pop();
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* int param_3 = obj.top();
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* boolean param_4 = obj.empty();
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*/
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```
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### **...**

‎solution/0200-0299/0225.Implement Stack using Queues/README_EN.md

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<p>Implement the following operations of a stack using queues.</p>
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<ul>
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<li>push(x) -- Push element x onto stack.</li>
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<li>pop() -- Removes the element on top of the stack.</li>
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<li>top() -- Get the top element.</li>
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<li>empty() -- Return whether the stack is empty.</li>
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</ul>
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<p><b>Example:</b></p>
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<p><b>Notes:</b></p>
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<ul>
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<li>You must use <i>only</i> standard operations of a queue -- which means only <code>push to back</code>, <code>peek/pop from front</code>, <code>size</code>, and <code>is empty</code> operations are valid.</li>
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<li>Depending on your language, queue may not be supported natively. You may simulate a queue by using a list or deque (double-ended queue), as long as you use only standard operations of a queue.</li>
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<li>You may assume that all operations are valid (for example, no pop or top operations will be called on an empty stack).</li>
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</ul>
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## Solutions
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### **Python3**
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```python
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class MyStack:
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def __init__(self):
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"""
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Initialize your data structure here.
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"""
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self.q = []
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def push(self, x: int) -> None:
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"""
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Push element x onto stack.
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"""
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self.q.append(x)
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n = len(self.q)
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for i in range(1, n):
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self.q.append(self.q.pop(0))
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def pop(self) -> int:
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"""
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Removes the element on top of the stack and returns that element.
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"""
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return self.q.pop(0)
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def top(self) -> int:
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"""
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Get the top element.
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"""
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return self.q[0]
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def empty(self) -> bool:
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"""
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Returns whether the stack is empty.
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"""
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return len(self.q) == 0
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# Your MyStack object will be instantiated and called as such:
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# obj = MyStack()
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# obj.push(x)
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# param_2 = obj.pop()
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# param_3 = obj.top()
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# param_4 = obj.empty()
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```
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### **Java**
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```java
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class MyStack {
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private Deque<Integer> q;
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/** Initialize your data structure here. */
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public MyStack() {
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q = new ArrayDeque<>();
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}
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/** Push element x onto stack. */
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public void push(int x) {
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q.offerLast(x);
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int n = q.size();
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while (n-- > 1) {
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q.offerLast(q.pollFirst());
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}
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}
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/** Removes the element on top of the stack and returns that element. */
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public int pop() {
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return q.pollFirst();
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}
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/** Get the top element. */
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public int top() {
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return q.peekFirst();
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}
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/** Returns whether the stack is empty. */
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public boolean empty() {
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return q.isEmpty();
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}
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}
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/**
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* Your MyStack object will be instantiated and called as such:
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* MyStack obj = new MyStack();
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* obj.push(x);
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* int param_2 = obj.pop();
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* int param_3 = obj.top();
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* boolean param_4 = obj.empty();
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*/
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```
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### **...**

‎solution/0200-0299/0225.Implement Stack using Queues/Solution.java

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class MyStack {
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class MyStack {
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Queue<Integer> q1;
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Queue<Integer> q2;
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private Deque<Integer> q;
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/** Initialize your data structure here. */
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public MyStack() {
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q1 = new LinkedList<>();
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q2 = new LinkedList<>();
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/** Initialize your data structure here. */
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public MyStack() {
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q = new ArrayDeque<>();
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}
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/** Push element x onto stack. */
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public void push(int x) {
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q.offerLast(x);
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int n = q.size();
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while (n-- > 1) {
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q.offerLast(q.pollFirst());
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}
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}
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/** Removes the element on top of the stack and returns that element. */
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public int pop() {
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return q.pollFirst();
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}
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/** Get the top element. */
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public int top() {
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return q.peekFirst();
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}
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/** Returns whether the stack is empty. */
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public boolean empty() {
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return q.isEmpty();
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}
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}
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/** Push element x onto stack. */
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public void push(int x) {
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q1.add(x);
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}
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/** Removes the element on top of the stack and returns that element. */
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public int pop() {
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if (q1.isEmpty()) {
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return 0;
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}
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while (q1.size() > 1) {
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q2.add(q1.poll());
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}
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int result = q1.poll();
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Queue<Integer> temp = q1;
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q1 = q2;
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q2 = temp;
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return result;
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}
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/** Get the top element. */
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public int top() {
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if (q1.isEmpty()) {
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return 0;
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}
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while (q1.size() > 1) {
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q2.add(q1.poll());
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}
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int result = q1.poll();
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q2.add(result);
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while (q2.size() > 0) {
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q1.add(q2.poll());
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}
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return result;
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}
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/** Returns whether the stack is empty. */
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public boolean empty() {
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return q1.isEmpty() && q2.isEmpty();
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}
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}
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/**
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* Your MyStack object will be instantiated and called as such:
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* MyStack obj = new MyStack();
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* obj.push(x);
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* int param_2 = obj.pop();
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* int param_3 = obj.top();
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* boolean param_4 = obj.empty();
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*/

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