45 lines
1015 B
Python
Executable File
45 lines
1015 B
Python
Executable File
#! /usr/bin/env python
|
|
|
|
import sys
|
|
import bitcoin
|
|
|
|
alphabet = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
|
|
|
|
|
|
def b58dec(word):
|
|
x = 0
|
|
for c in word:
|
|
x *= 58
|
|
x += alphabet.find(c)
|
|
return x
|
|
|
|
def asciidec(val):
|
|
word = []
|
|
while val > 0:
|
|
word.append(val % 256)
|
|
val /= 256
|
|
return word[-1::-1]
|
|
|
|
if __name__ == '__main__':
|
|
|
|
prefix = sys.argv[1]
|
|
length = int(sys.argv[2])
|
|
target = b58dec(prefix)
|
|
|
|
shift = 8*(length+4)
|
|
|
|
for m in range(1,1000):
|
|
lo = target * 58**m
|
|
lo = (lo >> shift) + (0 if lo == ((lo >> shift) << shift) else 1)
|
|
hi = (target + 1) * 58**m - (1 << shift) +1
|
|
hi = hi >> shift
|
|
if hi >= lo:
|
|
# test
|
|
for bt in '\x00\xff':
|
|
s = bitcoin.bin_to_b58check(bt * length, magicbyte=lo)
|
|
assert s.startswith(prefix)
|
|
assert len(s) == m + len(prefix)
|
|
|
|
print m + len(prefix), lo, asciidec(lo)
|
|
exit(0)
|