在一個basicds模塊裏用實現了兩個類：Stack和Queue及其各自所支持的操作。
隊列是以排隊的形式先進先出的序列集，棧是後進先出的序列集。
以下是模塊basicds模塊源碼：basicds.py
Python語言: 高亮代碼由發芽網提供
01 class Stack(object) :
02 def __init__(self) :
03 self.stack = []
04
05 def push(self, item) :
06 self.stack.append(item)
07
08 def pop(self) :
09 if self.stack != [] :
10 return self.stack.pop(-1)
11 else :
12 return None
13
14 def top(self) :
15 if self.stack != [] :
16 return self.stack[-1]
17 else :
18 return None
19
20 def length(self) :
21 return len(self.stack)
22
23 def isempty(self) :
24 return self.stack == []
25
26
27 class Queue(object) :
28 def __init__(self) :
29 self.queue = []
30
31 def enqueue(self, item) :
32 self.queue.append(item)
33
34 def dequeue(self) :
35 if self.queue != [] :
36 return self.queue.pop(0)
37 else :
38 return None
39
40 def head(self) :
41 if self.queue != [] :
42 return self.queue[0]
43 else :
44 return None
45
46 def tail(self) :
47 if self.queue != [] :
48 return self.queue[-1]
49 else :
50 return None
51
52 def length(self) :
53 return len(self.queue)
54
55 def isempty(self) :
56 return self.queue == []
02 def __init__(self) :
03 self.stack = []
04
05 def push(self, item) :
06 self.stack.append(item)
07
08 def pop(self) :
09 if self.stack != [] :
10 return self.stack.pop(-1)
11 else :
12 return None
13
14 def top(self) :
15 if self.stack != [] :
16 return self.stack[-1]
17 else :
18 return None
19
20 def length(self) :
21 return len(self.stack)
22
23 def isempty(self) :
24 return self.stack == []
25
26
27 class Queue(object) :
28 def __init__(self) :
29 self.queue = []
30
31 def enqueue(self, item) :
32 self.queue.append(item)
33
34 def dequeue(self) :
35 if self.queue != [] :
36 return self.queue.pop(0)
37 else :
38 return None
39
40 def head(self) :
41 if self.queue != [] :
42 return self.queue[0]
43 else :
44 return None
45
46 def tail(self) :
47 if self.queue != [] :
48 return self.queue[-1]
49 else :
50 return None
51
52 def length(self) :
53 return len(self.queue)
54
55 def isempty(self) :
56 return self.queue == []
代碼很簡單，不解釋不註釋，呵呵～
使用例程：
注意basicds.py必須放在Python解釋器可以搜索的路徑裏（使用import時會搜索模塊），這裏basicds.py和example.py在同一個目錄下，屬於Python解釋器可搜索範圍。
example.py
Python語言: 高亮代碼由發芽網提供
01 #!/usr/bin/env python
02
03 import basicds
04
05 s = basicds.Stack() # get a stack
06 q = basicds.Queue() # get a queue
07
08
09 for i in range(10) :
10 s.push(i)
11 q.enqueue(i)
12
13 # stack s
14 print 'length of stack s is %d' %s.length()
15 print 'top of stack s is %d' %s.top()
16 print 'pop an item %d from stack s' %s.pop()
17 print 'now, top of stack s is %d' %s.top()
18
19 print '\n'
20
21 #queue q
22 print 'length of queue q is %d' %q.length()
23 print 'head of queue q is %d' %q.head()
24 print 'tail of queue q is %d' %q.tail()
25 print 'del an item %d from queue q' %q.dequeue()
26 print 'now, head of queue q is %d' %q.head()
27 print 'tail of queue q is %d' %q.tail()
02
03 import basicds
04
05 s = basicds.Stack() # get a stack
06 q = basicds.Queue() # get a queue
07
08
09 for i in range(10) :
10 s.push(i)
11 q.enqueue(i)
12
13 # stack s
14 print 'length of stack s is %d' %s.length()
15 print 'top of stack s is %d' %s.top()
16 print 'pop an item %d from stack s' %s.pop()
17 print 'now, top of stack s is %d' %s.top()
18
19 print '\n'
20
21 #queue q
22 print 'length of queue q is %d' %q.length()
23 print 'head of queue q is %d' %q.head()
24 print 'tail of queue q is %d' %q.tail()
25 print 'del an item %d from queue q' %q.dequeue()
26 print 'now, head of queue q is %d' %q.head()
27 print 'tail of queue q is %d' %q.tail()
運行結果：
