添加0232用栈实现队列 python3 版本

problems/0232.用栈实现队列.md

@@ -282,6 +282,50 @@ class MyQueue {
 
 
 Python：
+```python
+# 使用两个栈实现先进先出的队列
+class MyQueue:
+    def __init__(self):
+        """
+        Initialize your data structure here.
+        """
+        self.stack1 = list()
+        self.stack2 = list()
+
+    def push(self, x: int) -> None:
+        """
+        Push element x to the back of queue.
+        """
+        # self.stack1用于接受元素
+        self.stack1.append(x)
+
+    def pop(self) -> int:
+        """
+        Removes the element from in front of queue and returns that element.
+        """
+        # self.stack2用于弹出元素，如果self.stack2为[],则将self.stack1中元素全部弹出给self.stack2
+        if self.stack2 == []:
+            while self.stack1:
+                tmp = self.stack1.pop()
+                self.stack2.append(tmp)
+        return self.stack2.pop()
+
+    def peek(self) -> int:
+        """
+        Get the front element.
+        """
+        if self.stack2 == []:
+            while self.stack1:
+                tmp = self.stack1.pop()
+                self.stack2.append(tmp)
+        return self.stack2[-1]
+
+    def empty(self) -> bool:
+        """
+        Returns whether the queue is empty.
+        """
+        return self.stack1 == [] and self.stack2 == []
+```
 
 
 Go：