import random
import math as floor


def genKys(length):
    length *= 8
    key = [0] * length
    choice = floor.floor(random.random() * length)
    for i in range(choice):
        key[floor.floor(random.random() * (length - 1))] = 1
    return key


def enc(plain, key):
    length = len(key)
    cipher = [None] * length
    for i in range(length):
        cipher[i] = 1 if key[i] == plain[i] else 0
    return cipher


def getBts(plain):
    length = len(plain)
    bits = [None] * length * 8
    for i in range(length):
        for j in range(8):
            bits[8 * i + 7 - j] = (int)(ord(plain[i]) / pow(2, j)) % 2
    return bits

def getBytes(bits):
    length = len(bits)
    data = []
    byte = 0
    for i in range((int)(length / 8)):
        for j in range(8):
            byte += pow(2, 7 - j) * bits[8 * i + j]
        data.append(byte)
        byte = 0
    return data

def toString(bytes):
    size = len(bytes)
    output = ""
    for i in range(size):
        output += chr(bytes[i])
    return output