def add_sybs(coll):
    return coll if len(coll) % 2 == 0 else coll + " "

def partition(coll, n):
    p = []
    for i in range(0, len(coll), n):
        p.append(coll[i:i+n])
    return p

def char2bin(letter):
    return bin(ord(letter))

def bin2char(binary):
    return chr(int(binary,2))

def bitshiftright(binary, n):
    b = binary
    for _ in range(n):
        b = b[-1:] + b[:-1]
    return b

def bitshiftleft(binary, n):
    b = binary
    for _ in range(n):
        b = b[1:] + b[:1]
    return b

def handle_binary(b, n):
    return ([0 for _ in range(n - (len(b) - 2))]
           + [int(el) for el in b[2:]])

def xor(b1, b2):
    return [0 if r1 == r2 else 1 for r1, r2 in zip(b1, b2)]

def make_block(pair, n):
    return [handle_binary(char2bin(pair[0]), n),
            handle_binary(char2bin(pair[1]), n)]

def make_blocks(text, n):
    pairs = partition(add_sybs(text), 2)
    return [make_block(pair, n) for pair in pairs]

def encode_block(block, key):
    l = block[0]
    r = block[1]
    return [xor(r, bitshiftright(l, key)), l]

def el_encode(blocks, key):
    return [encode_block(block, key) for block in blocks]

def list2str(arr):
    return ''.join([str(el) for el in arr])

def block2str(block):
    return (bin2char(list2str(block[0])) +
           bin2char(list2str(block[1])))

def blocks2str(blocks):
    return ''.join([block2str(block) for block in blocks])

def last_round(block, key):
    l = block[0]
    r = block[1]
    return [l, xor(r, bitshiftright(l, key))]

def my_encode(text, n, key, k):
    blocks = make_blocks(text, n)
    for _ in range(k-1):
        print(blocks[0])
        blocks = el_encode(blocks, key)
    print(blocks[0])
    return [last_round(block, key) for block in blocks]

def last_swap(block):
    return [block[1], block[0]]

def my_decode(blocks, key, k):
    for _ in range(k):
        blocks = el_encode(blocks, key)
    return [last_swap(block) for block in blocks]

text = "Кто не работает тот не ест"

encoded_text = my_encode(text, 16, 4, 2)

print(blocks2str(encoded_text))
print(blocks2str(my_decode(encoded_text, 4, 2)))