from pwn import *
host = 'notadmin.challs.cyberchallenge.it'
port = 9032

def hex_to_bin(hex_str: str) -> str:
    return "".join(bin(int(c, 16))[2:].zfill(4) for c in hex_str)


def bin_to_hex(bin_str: str) -> str:
    if len(bin_str) % 4 != 0:
        bin_str = bin_str.zfill(len(bin_str) + (4 - len(bin_str) % 4))
    return "".join(
        hex(int(bin_str[i:i+4], 2))[2:]
        for i in range(0, len(bin_str), 4)
    )