JZTXT

数据结构与算法-栈

发布时间 2023-06-07 18:55:45作者: 韩志超

栈

堆和栈一样吗?
栈(stack)一般编译器自动分配释放
堆(heap)一般由程序员分配释放,或程序结束后OS释放
LIFO 后进先出

栈的实现

class Stack(object):
    def __init__(self):
        self.__list = []
    def push(self, item):
        self.__list.append(item)

    def pop(self):
        return self.__list.pop()

    def peek(self):
        if self.__list:
            return self.__list[-1]
        else:
            return None

    def is_empoty(self):
        return self.__list == []

    def size(self):
        return len(self.__list)

if __name__ == '__main__':
    s = Stack()
    a = "({[({{abc}})][{1}]})2([]){({[]})}[]"
    m = {')':'(',']':'[','}':'{'}
    for i in a:
        if i in '([{':
            s.push(i)
        elif i in m:
            if m[i] != s.pop():
                print("fail")
                break
    else:
        print("ok")