| import random | |
| def str_xor(secret, key): | |
| #extend key to secret length | |
| new_key = key | |
| i = 0 | |
| while len(new_key) < len(secret): | |
| new_key = new_key + key[i] | |
| i = (i + 1) % len(key) | |
| return "".join([chr(ord(secret_c) ^ ord(new_key_c)) for (secret_c,new_key_c) in zip(secret,new_key)]) | |
| flag_enc = chr(0x15) + chr(0x07) + chr(0x08) + chr(0x06) + chr(0x27) + chr(0x21) + chr(0x23) + chr(0x15) + chr(0x5f) + chr(0x05) + chr(0x08) + chr(0x2a) + chr(0x1c) + chr(0x5e) + chr(0x1e) + chr(0x1b) + chr(0x3b) + chr(0x17) + chr(0x51) + chr(0x5b) + chr(0x58) + chr(0x5c) + chr(0x3b) + chr(0x42) + chr(0x57) + chr(0x5c) + chr(0x0d) + chr(0x5f) + chr(0x06) + chr(0x46) + chr(0x5c) + chr(0x13) | |
| num = random.choice(range(10,101)) | |
| print('If ' + str(num) + ' is in decimal base, what is it in binary base?') | |
| ans = input('Answer: ') | |
| try: | |
| ans_num = int(ans, base=2) | |
| if ans_num == num: | |
| flag = str_xor(flag_enc, 'enkidu') | |
| print('That is correct! Here\'s your flag: ' + flag) | |
| else: | |
| print(str(ans_num) + ' and ' + str(num) + ' are not equal.') | |
| except ValueError: | |
| print('That isn\'t a binary number. Binary numbers contain only 1\'s and 0\'s') | |