diff options
Diffstat (limited to 'servo')
| -rw-r--r-- | servo/lib/shorturl.py | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/servo/lib/shorturl.py b/servo/lib/shorturl.py index f93028f..a78c699 100644 --- a/servo/lib/shorturl.py +++ b/servo/lib/shorturl.py @@ -56,42 +56,53 @@ class UrlEncoder(object): self.alphabet = alphabet self.block_size = block_size self.mask = (1 << block_size) - 1 - self.mapping = range(block_size) + self.mapping = list(range(block_size)) self.mapping.reverse() + def encode_url(self, n, min_length=MIN_LENGTH): return self.enbase(self.encode(n), min_length) + def decode_url(self, n): return self.decode(self.debase(n)) + def encode(self, n): return (n & ~self.mask) | self._encode(n & self.mask) + def _encode(self, n): result = 0 for i, b in enumerate(self.mapping): if n & (1 << i): result |= (1 << b) return result + def decode(self, n): return (n & ~self.mask) | self._decode(n & self.mask) + def _decode(self, n): result = 0 for i, b in enumerate(self.mapping): if n & (1 << b): result |= (1 << i) return result + def enbase(self, x, min_length=MIN_LENGTH): result = self._enbase(x) padding = self.alphabet[0] * (min_length - len(result)) return '%s%s' % (padding, result) + def _enbase(self, x): + x = int(x) n = len(self.alphabet) if x < n: return self.alphabet[x] return self._enbase(x / n) + self.alphabet[x % n] + def debase(self, x): n = len(self.alphabet) result = 0 for i, c in enumerate(reversed(x)): result += self.alphabet.index(c) * (n ** i) + return result DEFAULT_ENCODER = UrlEncoder() @@ -127,4 +138,4 @@ if __name__ == '__main__': assert a == e assert b == d c = (' ' * (7 - len(c))) + c - print '%6d %12d %s %12d %6d' % (a, b, c, d, e) + print ('%6d %12d %s %12d %6d' % (a, b, c, d, e)) |