python-数据结构代码 双端队列

from pythonds.basic.deque import Deque
class Deque:
    def __init__(self):
        self.items = []

    def isEmpty(self):
        return self.items == []

    def addFront(self, item):
        self.items.append(item)

    def addRear(self, item):
        self.items.insert(0,item)

    def removeFront(self):
        return self.items.pop()

    def removeRear(self):
        return self.items.pop(0)

    def size(self):
        return len(self.items)
def palchecker(aString):
    chardeque=Deque()
    for ch in aString:
        chardeque.addRear(ch)
    stillEqual=True
    while chardeque.size()>1 and stillEqual:
        first=chardeque.removeFront()
        last=chardeque.removeRear()
        if first!=last:
            stillEqual=False
    return stillEqual
print(palchecker("lsdkjfskf"))
print(palchecker("radar"))