Add typing annotations to Python codes. (#411)

codes/python/chapter_stack_and_queue/deque.py

@@ -4,19 +4,15 @@ Created Time: 2022-11-29
 Author: Peng Chen (pengchzn@gmail.com)
 """
 
-import os.path as osp
-import sys
-
+import sys, os.path as osp
 sys.path.append(osp.dirname(osp.dirname(osp.abspath(__file__))))
 from modules import *
 
-from collections import deque
-
 
 """ Driver Code """
 if __name__ == "__main__":
     """ 初始化双向队列 """
-    deque = deque()
+    deque: Deque[int] = collections.deque()
 
     """ 元素入队 """
     deque.append(2)      # 添加至队尾
@@ -27,23 +23,23 @@ if __name__ == "__main__":
     print("双向队列 deque =", deque)
 
     """ 访问元素 """
-    front = deque[0]  # 队首元素
+    front: int = deque[0]  # 队首元素
     print("队首元素 front =", front)
-    rear = deque[-1]  # 队尾元素
+    rear: int = deque[-1]  # 队尾元素
     print("队尾元素 rear =", rear)
 
     """ 元素出队 """
-    pop_front = deque.popleft()  # 队首元素出队
+    pop_front: int = deque.popleft()  # 队首元素出队
     print("队首出队元素  pop_front =", pop_front)
     print("队首出队后 deque =", deque)
-    pop_rear = deque.pop()       # 队尾元素出队
+    pop_rear: int = deque.pop()       # 队尾元素出队
     print("队尾出队元素  pop_rear =", pop_rear)
     print("队尾出队后 deque =", deque)
 
     """ 获取双向队列的长度 """
-    size = len(deque)
+    size: int = len(deque)
     print("双向队列长度 size =", size)
 
     """ 判断双向队列是否为空 """
-    is_empty = len(deque) == 0
+    is_empty: bool = len(deque) == 0
     print("双向队列是否为空 =", is_empty)