How can I move every other letter of a string

Question

I would like help with one cipher, specifically such that I have words/letters and each shift by a certain number

example word Example

+1 input number
output is

example

+2 input numbers
output is

Eapexml

I have this script but it only works for two shifit

def encrypt(message,shift):
   return "%s%s" % (message[::shift],message[1::shift])


print(encrypt("123456",2))

135246

and I really need other combinations

(preferably according to how they are written in the object)

number [1,2,3,4,5,6,7,8,9,10,11] this is just an example, I will also use other numbers like prime etc…

but I don’t know how to write the script, could someone help me?

Asked By: Nobikk

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Source

Answer 1

I think this is what you’re trying to do:

def encrypt(message, shift):
    return ''.join(message[i::shift] for i in range(shift)) if shift > 1 else message

for i in range(1, 5):
    print(encrypt('ABCDEFGH', i))

Output:

ABCDEFGH
ACEGBDFH
ADGBEHCF
AEBFCGDH

Observation:

This is an awful encryption algorithm if only because the first letter never changes

Answered By: Stuart

Answer 2

Wanted to see if this is possible with a regular expression for fun:

import regex as re

def encrypt(message,shift):
    rgx = re.compile(fr'(?:.{{{shift-1}}}|.G)K.')
    return re.sub(rgx, '', message) + ''.join(re.findall(rgx, message))

for i in range(1, 5):
    print(encrypt('example', i))

Prints:

example
eapexml
exmpeal
exaplem

Answered By: JvdV

How can I move every other letter of a string

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