encrypt

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#!/usr/bin/env python
# -*- coding: utf-8 -*-

def encode(ciphertext):
    flag = '*************' 
    ciphertext = []
    for i in range(len(flag)): 
        s = chr(i ^ ord(flag[i]))  
        if i % 2 == 0:
            s = ord(s) + 10
        else:
            s = ord(s) - 10
        ciphertext.append(str(s))
    
    return ciphertext[::-1]

ciphertext = [  # 24
    '96',
    '65',
    '93',
    '123',
    '91',
    '97',
    '22',
    '93',
    '70',
    '102',
    '94',
    '132',
    '46',
    '112',
    '64',
    '97',
    '88',
    '80',
    '82',
    '137',
    '90',
    '109',
    '99',
    '112']

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#!/usr/bin/env python
# -*- coding: utf-8 -*-

def decode(ciphertext):
    flag = ''
    ciphertext.reverse()
    for i in range(len(ciphertext)):
        if i % 2 == 0:
            s = int(ciphertext[i])-10
        else:
            s = int(ciphertext[i])+10

        flag += chr(i^s)
    return flag 

ciphertext = [
    '96',
    '65',
    '93',
    '123',
    '91',
    '97',
    '22',
    '93',
    '70',
    '102',
    '94',
    '132',
    '46',
    '112',
    '64',
    '97',
    '88',
    '80',
    '82',
    '137',
    '90',
    '109',
    '99',
    '112']

if __name__ == '__main__':
    f = decode(ciphertext)
    print(f)