Trie.py

"""
@version: python3.6
@author: Fieldhunter
@contact: 1677532160yuan@gmail.com
@time: 2020-05-03
"""
import functools


class Trie_Node():
    """
        The string types stored in the Trie contain
          only 26 English lowercase letters.
    """
    def __init__(self, string):
        self.data = string
        self.next = [None] * 26
        self.end = False

class Trie():
    def __init__(self):
        self.__head = Trie_Node(None)

    def add_data(self, string):
        pointer = self.__head

        for character in string:
            character_ascll = ord(character) - 97
            if pointer.next[character_ascll] == None:
                new_node = Trie_Node(character)
                pointer.next[character_ascll] = new_node
            pointer = pointer.next[character_ascll]

        pointer.end = True

    def find_data(self, string):
        pointer = self.__head
        find = False

        for character in string:
            character_ascll = ord(character) - 97
            if pointer.next[character_ascll] == None:
                break
            pointer = pointer.next[character_ascll]
            if character == string[-1]:
                if pointer.end == True:
                    find = True

        if find:
            print("Find target data")
        else:
            print("No target data")

    """
        Check if the code used to access the self.__head, Decorator function.
        The purpose of simply adding code is to prevent Trie from 
          being tampered with maliciously and to provide the API for developers.
    """
    def __check_code(func):
        @functools.wraps(func)
        def check(self, code):
            if code != 'adsf;{h3096j34ka`fd>&/edgb^45:6':
                raise Exception('code is wrong!')
            result = func(self, code)
            return result

        return check

    @__check_code
    def return_head(self, code):
        return self.__head