# based on https://github.com/boppreh/aes/blob/master/aes.py
from flag import flag, key
import copy
KEY_SIZE = 2
ROUNDS = 100

def sub_bytes(s):
    for i in range(2):
        s[i][0] = sbox[s[i][0]]

def final_sub(s):
    for i in range(2):
        s[i][1] = sbox[s[i][1]]

sbox = [0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5, 0x30, 0x01, 0x67, 0x2B, 0xFE, 0xD7, 0xAB, 0x76,
        0xCA, 0x82, 0xC9, 0x7D, 0xFA, 0x59, 0x47, 0xF0, 0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4, 0x72, 0xC0,
        0xB7, 0xFD, 0x93, 0x26, 0x36, 0x3F, 0xF7, 0xCC, 0x34, 0xA5, 0xE5, 0xF1, 0x71, 0xD8, 0x31, 0x15,
        0x04, 0xC7, 0x23, 0xC3, 0x18, 0x96, 0x05, 0x9A, 0x07, 0x12, 0x80, 0xE2, 0xEB, 0x27, 0xB2, 0x75,
        0x09, 0x83, 0x2C, 0x1A, 0x1B, 0x6E, 0x5A, 0xA0, 0x52, 0x3B, 0xD6, 0xB3, 0x29, 0xE3, 0x2F, 0x84,
        0x53, 0xD1, 0x00, 0xED, 0x20, 0xFC, 0xB1, 0x5B, 0x6A, 0xCB, 0xBE, 0x39, 0x4A, 0x4C, 0x58, 0xCF,
        0xD0, 0xEF, 0xAA, 0xFB, 0x43, 0x4D, 0x33, 0x85, 0x45, 0xF9, 0x02, 0x7F, 0x50, 0x3C, 0x9F, 0xA8,
        0x51, 0xA3, 0x40, 0x8F, 0x92, 0x9D, 0x38, 0xF5, 0xBC, 0xB6, 0xDA, 0x21, 0x10, 0xFF, 0xF3, 0xD2,
        0xCD, 0x0C, 0x13, 0xEC, 0x5F, 0x97, 0x44, 0x17, 0xC4, 0xA7, 0x7E, 0x3D, 0x64, 0x5D, 0x19, 0x73,
        0x60, 0x81, 0x4F, 0xDC, 0x22, 0x2A, 0x90, 0x88, 0x46, 0xEE, 0xB8, 0x14, 0xDE, 0x5E, 0x0B, 0xDB,
        0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C, 0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79,
        0xE7, 0xC8, 0x37, 0x6D, 0x8D, 0xD5, 0x4E, 0xA9, 0x6C, 0x56, 0xF4, 0xEA, 0x65, 0x7A, 0xAE, 0x08,
        0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6, 0xE8, 0xDD, 0x74, 0x1F, 0x4B, 0xBD, 0x8B, 0x8A,
        0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E, 0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E,
        0xE1, 0xF8, 0x98, 0x11, 0x69, 0xD9, 0x8E, 0x94, 0x9B, 0x1E, 0x87, 0xE9, 0xCE, 0x55, 0x28, 0xDF,
        0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68, 0x41, 0x99, 0x2D, 0x0F, 0xB0, 0x54, 0xBB, 0x16]

def shift_rows(s):
    s[0][0], s[1][0] = s[1][0], s[0][0]

def final_shift(s):
    s[0][1], s[1][1] = s[1][1], s[0][1]

def mix_column(column):
    column[0] = column[0] ^ column[1]
  
def mix_columns(state):
    for i in range(2):
        column = []
        for j in range(2): column.append(state[i][j])
        mix_column(column)
        for j in range(2): state[i][j] = column[j]

def add_round_key(s, k):
    for i in range(2):
        for j in range(2):
            s[i][j] ^= k[k[k[k[i*2+j]%4]%4]%4]

def final_add(s, k):
    for i in range(2):
        s[i][1] ^= k[k[k[k[i*2+1]%4]%4]%4]

def schedule_key(k):
    for i in range(4):
        for j in range(2*ROUNDS):
            k[i] = pow(pow(sbox[sbox[sbox[((((k[i] << 4) ^ k[i]) << 4) ^ k[i]) % 256]]], pow(k[i], k[i]), 256), pow(sbox[k[i]], sbox[k[i]]), 256)

def final_schedule(k):
    for i in range(4):
        k[i] = sbox[k[i]]

def bytes2matrix(text):
    return [list(text[i:i+2]) for i in range(0, len(text), 2)]

def matrix2bytes(matrix):
    return bytes(sum(matrix, []))

def pad(plaintext):
    padding_len = 4 - (len(plaintext) % 4)
    padding = bytes([padding_len] * padding_len)
    return plaintext + padding

def unpad(plaintext):
    padding_len = plaintext[-1]
    assert padding_len > 0
    message, padding = plaintext[:-padding_len], plaintext[-padding_len:]
    assert all(p == padding_len for p in padding)
    return message

def split_blocks(message, block_size=4, require_padding=True):
        assert len(message) % block_size == 0 or not require_padding
        return [message[i:i+4] for i in range(0, len(message), block_size)]

def encrypt(p, k):
    ciphertext = b""
    for i in split_blocks(pad(p)):
        key = k.copy()
        i = bytes2matrix(i)
        add_round_key(i, key)
        for j in range(ROUNDS):
            schedule_key(key)
            sub_bytes(i)
            shift_rows(i)
            mix_columns(i)
            add_round_key(i, key)
        final_schedule(key)
        final_sub(i)
        final_shift(i)
        final_add(i, key)
        ciphertext += matrix2bytes(i)
    return ciphertext


print(encrypt(flag, key).hex())