Rating:
These are standard encodings from binary (b) to hexadecimal (x). We can use Python's built-in parser for these common forms (except for decimal).
For example:
```python
>>> int('0b111000', 0)
56
>>> chr(56)
'8
```
__Solution:__
```python
with open('30.txt') as message:
codes = message.readline().split()
ans = [int('0{}'.format(e), 0) if e[0] != 'd' else int(e[1:]) for e in codes]
ans = [chr(e) for e in ans]
print(''.join(ans))
```
__Output:__
```
Hi! Welcome to HackCon'18, organised as part of Esya'18 by IIIT Delhi. In case you're seeking a reward for your efforts, here's a flag : d4rk{i_Wis#_A1l_t4sk5_w3r3_thi5_345y_XDD}c0de. Anyways, hope you have a good time ;)
```
__Flag:__
```
d4rk{i_Wis#_A1l_t4sk5_w3r3_thi5_345y_XDD}c0de
```
