字符串堆栈和队列

字符串堆栈程序

 

#!/user/bin/env python
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 'Removed [',stack.pop(),']'
def viewstack():
    print stack #calls str() internally
CMDs={'u':pushit,'o':popit,'v':viewstack}
def showmenu():
    pr="""
    p(U)sh
    p(O)p
    (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 'uovq':
                print 'Invalid option,try again'
            else:
                break
        if choice=='q':
            break
        CMDs[choice]()
if __name__=='__main__':
    showmenu()

 

字符串队列程序

#!/user/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 [',queue.pop(0),']'
def viewQ():
    print queue #calls str() internally
CMDs={'e':enQ,'d':deQ,'v':viewQ}
def showmenu():
    pr="""
(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()