Exercice 7

[DominiqueMakowski]

Add a decoder feature
Post your solution as a comment to the discussion

Expected:

>>> x = decoder(“Hello World”, encode=True)
>>> print(x)
“ifmmp xpsme”

>>> y = decoder(“ifmmp xpsme”)
>>> print(y)
“hello world”

[rejoha]

def transform_string(string, encode):
    """ Transform each letter into the next or previous letter in the alphabet, dpending on if encode is true or false. """
    if encode == True:
        trans = 1
        end = 0
    else:
        trans = -1
        end = -1
    alphabet =  ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"]
    new_string = ''
    for l in string:
        if l.lower() in alphabet:
            try:
                i = alphabet.index(l.lower())
                new_string += alphabet[i + trans]
            except IndexError:
                new_string += alphabet[end]
        else:
            new_string += l

    return new_string

[rejoha]

Since it doesn't make sense to split my code in that way, I have instead split it the other way around. Principle remains the same, though it wouldn't make much sense/reduce code:

def transform_string(string, trans, end):
    """ Transform each letter into the next letter in the alphabet. 
    Other symbols/spaces remain the same, and the last letter of the alphabet becomes the first letter. """
    alphabet =  ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"]
    new_string = ''
    for l in string:
        if l.lower() in alphabet:
            try:
                i = alphabet.index(l.lower())
                new_string += alphabet[i + trans]
            except IndexError:
                new_string += alphabet[end]
        else:
            new_string += l

    return new_string


def trans_up(string):
    trans = 1
    end = 0

    return transform_string(string, trans, end)

def trans_down(string):
    trans = -1
    end = -1

    return transform_string(string, trans, end)

trans_up('Hello world!')
trans_down('Hello world!')

[Cymelo92]

def decoder(s, encode=False):
    s = s.lower()
    alphabet =  ["a", "b", "c", "d", "e", "f", "g", 
    "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", 
    "r", "s", "t", "u", "v", "w", "x", "y", "z"]
    sentence = ""
    if encode==False:
        for letter in s:
            if letter == " ":
                sentence += " "
            elif letter == "a":
                sentence += "z"
            else:
                sentence += alphabet[alphabet.index(letter)-1]
        return sentence
    else:
        return s

[SvennoNito]

import string

def shift_word_byone(word, encode=True):

    alphabet    = list(string.ascii_lowercase)
    output      = ""

    if encode:
        shift = -1
    else:
        shift = 1

    for iword, vword in enumerate(word.lower()):

        # Edge case
        if iword == 0 & shift == -1:       
            iword = len(alphabet) + 1
        elif iword == len(alphabet) & shift == 1:
            iword = -1       

        previous_ndx    = alphabet.index(vword) + shift
        output += alphabet[previous_ndx]

    return output



shift_word_byone("ifmmp", encode=True)

[AnaRodMa]

def enc_3 (word, dec):
    final = ''
    alphabet = ["a", "b", "c", "d", "e", "f", "g", 
        "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", 
        "r", "s", "t", "u", "v", "w", "x", "y", "z"]
           
    for j in word:        
        if j == 'z':
            let = 'a'
            final += let
        else:
            ind = alphabet.index(j) 
            if dec == True:                                  
                letter = ind + 1
            else:
                letter = ind - 1

            final += alphabet[letter]
    return final

[floramouj]

def decoder(x, encode=False):
        alphabet =  ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"]
        x = x.lower()
        sentence = ""
        if encode is True:
            for letter in x:
                if letter == "z":
                    sentence += "a"
                elif letter == " ":
                    sentence += " "
                else:
                    sentence += alphabet[alphabet.index(letter)+1]
        if encode is False:
            for letter in x:
                if letter == "a":
                    sentence += "z"
                elif letter == " ":
                    sentence += " "
                else:
                    sentence += alphabet[alphabet.index(letter)-1]
        return sentence
            
decoder("hppe npsojoh", encode=False)

[MartynaPlomecka]

alph=  ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"]

def decoder(x, encode=True):
    x = x.lower()
    word = ""
    if encode==False:
        for l in x:
            if l == "a":
                word += "z"
            else:
                word += alph[alph.index(l)-1]
        return word
    else:
        return x

decoder("hello")