#!/usr/bin/python

import subprocess
import math
import hashlib
import base64
from itertools import chain, product
from zipfile import ZipFile

# for x in ["Dasher", "Dancer", "Prancer", "Vixen", "Comet", "Cupid", "Donder", "Blitzen"]:
#     subprocess.call(["unzip", "-P", x, "z.zip"])


# print(bytes(int(x) for x in "5 8 16 20 27".split(" ")).decode("cp500"))

# x = [chr(i + ord('a')) for i in range(0, 26)] + [chr(i + ord('A')) for i in range(0, 26)] + [str(i) for i in range(10)]
# print(x)
#
# try:
#     for s in x:
#         data = ZipFile.open("Final_easy.zip", mode='r', pwd=s)
#         if data != '':
#             print("found pw")
# except:
#     pass


# we know that b * c = 6497 and b < c
prod = 6497
for b in range(2,math.floor(math.sqrt(prod))):
    if math.floor(prod / b) == prod / b:
        c = prod // b
        break

# which gives us:
# b = 73
# c = 89
# print("b=%d c=%d" % (b, c))

hash = "CF945B5A36D1D3E68FFF78829CC8DBF6".lower()
hash_reversed = "H0b0"

def bruteforce(charset, minlength, maxlength):
    return (''.join(candidate)
        for candidate in chain.from_iterable(product(charset, repeat=i)
        for i in range(1, maxlength + 1)))

# alphabet = 'abcdefghiklmnopqrstuvwxyz'
# alphabet += alphabet.upper()
# alphabet += ''.join([str(i) for i in range(10)])
#
# for i in bruteforce(alphabet, 4, 4):
#     try:
#         m = hashlib.md5()
#         m.update(i.encode("utf-8"))
#         new_hash = m.hexdigest()
#         if new_hash == hash:
#             hash_reversed = i
#             break
#     except:
#         pass

if hash_reversed == None:
    exit("could not find hash")

# Step 3: squareRoot
squareRoot = int(math.sqrt(8814961))

# Step 4: XOR
result = 'zvru'
part3 = ''.join([chr(ord(result[i]) ^ ord(str(squareRoot)[i])) for i in range(4)])
# print(part3)

# Step 5: Base64
b64 = base64.b64decode('RjBtMA==').decode("utf-8")
# print(b64)

flag = "HV18-%02d%02d-%s-%s-%04d-%s" % (b, c, hash_reversed, part3, squareRoot, b64)
print(flag)