import struct

# Open the file for reading in binary mode
with open("flag.enc", "rb") as f:
    # Read the first 4 bytes, which represent the seed
    seed_bytes = f.read(4)
    # Unpack the seed as a 32-bit unsigned integer
    seed = struct.unpack("I", seed_bytes)[0]
    # Read the rest of the file contents
    enc_data = f.read()

print(f"seed: {seed}, hex: {hex(seed)}")
print(f"enc_data: {enc_data}")

# Use the seed to seed the random number generator
import random
random.seed(seed)

# Allocate a buffer for the decrypted data
dec_data = bytearray(len(enc_data))

# Perform the decryption
for i in range(len(enc_data)):
    # XOR with a random byte
    dec_data[i] = enc_data[i] ^ random.getrandbits(8)
    # Perform the inverse bit-shift operation
    shift = random.randint(0,7)
    dec_data[i] = ((dec_data[i] >> shift) | (dec_data[i] << (8 - shift))) % 256

print(f"flag: {dec_data}")

# Write the decrypted data to a file
# with open("flag.dec", "wb") as f:
#     f.write(dec_data)