栈是一种后进先出(LIFO)的数据结构。你可以通过push操作来向栈中添加一个对象，也可以通过pop操作来返回并删除栈顶对象。
以下是列表模拟栈的代码：
<span style="font-size:14px;">#!/usr/bin/env python
'stack.py create a stack'
stack = []
def pushit():
stack.append(raw_input('Enter New string: ').strip())
def popit():
if len (stack) == 0:
print 'Cannot pop from an empty stack!'
else:
print 'Remove [', repr(stack.pop()), ']'
def viewstack():
print stack
CMDs = {'u': pushit, 'o':popit, 'v': viewstack}
def showmenu():
pr = '''
push<span style="white-space:pre"> </span>#u represent push
pop<span style="white-space:pre"> </span>#o represent pop
view<span style="white-space:pre"> </span>#v represent view
quit<span style="white-space:pre"> </span>#q represent quit
Enter choice: '''
while True:
while True:
try:
choice = raw_input(pr).strip()[0].lower()
except (EOFError, KeyboardInterrupt, IndexError):
choice = 'q'
print '\nYou picked: [%s]' % choice
if choice not in 'uovq':
print 'Invalid option, try again'
else:
break
if choice == 'q':
break;
CMDs[choice]()
if __name__ == '__main__':
showmenu()
</span>
下面是运行结果：
<span style="font-size:14px;">likai@linux-ne7w:~/python> python stack.py
push
pop
view
quit
Enter choice: v
You picked: [v]
[]
push
pop
view
quit
Enter choice: p
You picked: [p]
Invalid option, try again
push
pop
view
quit
Enter choice: u
You picked: [u]
Enter New string: one
push
pop
view
quit
Enter choice: u
You picked: [u]
Enter New string: two
push
pop
view
quit
Enter choice: u
You picked: [u]
Enter New string: three
push
pop
view
quit
Enter choice: v
You picked: [v]
['one', 'two', 'three']
push
pop
view
quit
Enter choice: o
You picked: [o]
Remove [ 'three' ]
push
pop
view
quit
Enter choice: v
You picked: [v]
['one', 'two']
push
pop
view
quit
Enter choice: p
You picked: [p]
Invalid option, try again
push
pop
view
quit
Enter choice: o
You picked: [o]
Remove [ 'two' ]
push
pop
view
quit
Enter choice: v
You picked: [v]
['one']
push
pop
view
quit
Enter choice:
</span>队列是一种先进先出(FIFO)的数据结构
以下是列表模拟队列的代码：
<span style="font-size:14px;">#!/usr/bin/env python
queue = []
def enQ():
queue.append(raw_input('Enter New string: ').strip())
def deQ():
if len(queue) == 0:
print 'Cannot pop from an empty queue!'
else:
print 'Removed [', repr(queue.pop(0)), ']'
def viewQ():
print queue #calls str() internaily
CMDS = {'e': enQ, 'd': deQ, 'v': viewQ}
def showmenu():
pr = '''</span>
<span style="font-size:14px;"> (E)nqueue
(D)equeue
(V)iew
(Q)uit
Enter choice: '''
while True:
while True:
try:
choice = raw_input(pr).strip()[0].lower()
except (EOFError, KeyboardInterrupt, IndexError):
choice = 'q'
print '\nYou picked: [%s]' % choice
if choice not in 'devq':
print 'Invalid option, try again'
else:
break
if choice == 'q':
break
CMDS[choice]()
if __name__ == '__main__':
showmenu()
</span>下面是运行结果：
<span style="font-size:14px;">likai@linux-ne7w:~/python> python queue.py
(E)nqueue
(D)equeue
(V)iew
(Q)uit
Enter choice: e
You picked: [e]
Enter New string: one
(E)nqueue
(D)equeue
(V)iew
(Q)uit
Enter choice: e
You picked: [e]
Enter New string: two
(E)nqueue
(D)equeue
(V)iew
(Q)uit
Enter choice: e
You picked: [e]
Enter New string: three
(E)nqueue
(D)equeue
(V)iew
(Q)uit
Enter choice: v
You picked: [v]
['one', 'two', 'three']
(E)nqueue
(D)equeue
(V)iew
(Q)uit
Enter choice: d
You picked: [d]
Removed [ 'one' ]
(E)nqueue
(D)equeue
(V)iew
(Q)uit
Enter choice: v
You picked: [v]
['two', 'three']
(E)nqueue
(D)equeue
(V)iew
(Q)uit
Enter choice: d
You picked: [d]
Removed [ 'two' ]
(E)nqueue
(D)equeue
(V)iew
(Q)uit
Enter choice: v
You picked: [v]
['three']
(E)nqueue
(D)equeue
(V)iew
(Q)uit
Enter choice:
</span>原文地址：http://blog.csdn.net/u012088213/article/details/44875959
