Created
October 30, 2013 06:26
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Python implementation for generating Tiny URL- and bit.ly-like URLs
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| #!/usr/bin/env python | |
| _alphabet = "qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM0123456789" | |
| _base = len(_alphabet) | |
| def encode(n): | |
| """ | |
| Encode a number using the alphabet above | |
| >>> encode(0) | |
| 'q' | |
| >>> encode(61) | |
| '9' | |
| >>> encode(23423) | |
| 'uyB' | |
| """ | |
| r = [] | |
| r1 = n / _base | |
| r2 = n % _base | |
| r.insert(0, r2) | |
| while r1 >= _base: | |
| n = r1 | |
| r1 = n / _base | |
| r2 = n % _base | |
| r.insert(0, r2) | |
| if r1: | |
| r.insert(0, r1) | |
| return "".join([_alphabet[i] for i in r]) | |
| def decode(s): | |
| """ | |
| Decode a string into a base 10 number | |
| >>> decode('q') | |
| 0 | |
| >>> decode('9') | |
| 61 | |
| >>> decode('uyB') | |
| 23423 | |
| """ | |
| s = s[::-1] | |
| return sum([_alphabet.index(i)*_base**s.index(i) for i in s]) | |
| if __name__ == "__main__": | |
| import doctest | |
| doctest.testmod() |
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