triee.py

# coding: utf-8
'''
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

                            Preamble

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  If the disclaimer of warranty and limitation of liability provided
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                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.

  To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

    This program is free software: you can redistribute it and/or modify
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    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
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    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
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Also add information on how to contact you by electronic and paper mail.

  If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:

    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<https://www.gnu.org/licenses/>.

  The GNU General Public License does not permit incorporating your program
into proprietary programs.  If your program is a subroutine library, you
may consider it more useful to permit linking proprietary applications with
the library.  If this is what you want to do, use the GNU Lesser General
Public License instead of this License.  But first, please read
<https://www.gnu.org/licenses/why-not-lgpl.html>.


'''

#node
class TrieNode(object):
    def __init__(self, char:str):
        self.char = char
        self.children = []
        self.wordFinished = False
        self.counter = 1



#adding a word
def addword(root, word:str):
    node = root
    #print(word)
    for char in word:
        found_in_child = False
        for child in node.children:
            if child.char == char:
                found_in_child = True
                child.counter += 1
                node = child
                break
        
        if not found_in_child:
            new_node = TrieNode(char)
            node.children.append(new_node)
            node = new_node
            #print(node.char)
    node.wordFinished = True




from typing import Tuple
def findPrefix(root, prefix: str) -> Tuple[bool, int]:
    node = root
    if not root.children:
        return False, 0
    for char in prefix:
        char_not_found = True
        for child in node.children:
            if child.char == char:
                print(child.counter,char)
                char_not_found = False
                node = child
                break
        if char_not_found:
            return False, 0
    return True , node.counter


# In[5]:


#f = open('untitled.txt', encoding='utf-8') 
import re
def getWords(text):
    return re.compile('\w+').findall(text)


# In[6]:


newroot = TrieNode("-")
a = []
def readWords(filename: str):
    with open(filename , encoding='utf-8') as f:
          for line in f:
            for k in getWords(line):
                addword(newroot, k.lower())



# function to find the last node
def findNode(root, prefix: str):
    node = root
    wor = prefix
    if not root.children:
        return 0
    for char in prefix:
        char_not_found = True
        for child in node.children:
            if child.char == char:
                char_not_found = False
                node = child
                break
                wor += char
        if char_not_found:
            return 0
    return node


# In[28]:


#node with largest countr value
def largeNode(root):
    count = 0
    for child in root.children:
        if child.counter >= count:
            larg_node = child
            count = child.counter
    return larg_node


# In[52]:


#finding words 
def findWords(root, word: str):
    word_in_node = findNode(root, word)
    stri = word
    while True:
            if not word_in_node.wordFinished:
                word_in_node = largeNode(word_in_node)
                stri += word_in_node.char 
                
            else:
                return stri

            


#adding words in reverse order
def addwordReverse(root, word: str):
    str = ""
    for i in word:
        str = i + str
    addword(root, str)

#to check whether a word is complete
def isComplete(root, word:str):
    if findNode(root, word).wordFinished:
        return True
    else:
        return False