python 在python中实现倒数第一个堆栈

Posted 2021-05-09

class stack(object):

    def __init__(self, values):
        self.values = [elem for elem in values]
    def __repr__(self):
        string = ''
        for i in reversed(range(len(self.values))):
            string += str(self.values[i]) + '\n'
        return string
    def __str__(self):
        return str(self.values)
    def first(self):
        return self.values[len(self.values)-1]
    def push(self, elem):
        self.values.append(elem)
    def pull(self):
        return self.values.pop()
    def is_empty(self):
        if self.values == []:
            return True
        else:
            return False

def search_stack(stack, elem):
    if stack.first() == elem:
        return True
    elif stack.is_empty():
        return False
    else:
        stack.pull()
        return search_stack(stack, elem)

def reverse_stack(stk):
    lst = []
    while stk.is_empty() == False:
        lst.append(stk.pull())
    new = stack(lst)
    return new