blob: 0fe66f054a5ac01a228ea4c1ebe050b3e9ad31b4 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
|
# SPDX-License-Identifier: BSD-2-Clause
# SPDX-FileCopyrightText: Copyright (c) 2025 Runxi Yu <https://runxiyu.org>
import base64
import hashlib
import sys
import struct
def validate_bit_zeros(bs: bytes, n: int) -> bool:
q, r = divmod(n, 8)
if any(b != 0 for b in bs[:q]):
return False
if r and (bs[q] & (0xFF << (8 - r))):
return False
return True
decoded = base64.b64decode(sys.argv[1])
difficulty = int(sys.argv[2])
next_val = 0
while True:
h = hashlib.sha256(decoded + struct.pack("Q", next_val)).digest()
if validate_bit_zeros(h, difficulty):
break
next_val = (next_val + 1) & 0xFFFFFFFFFFFFFFFF
if next_val == 0:
raise ValueError("overflow")
print(base64.b64encode(struct.pack("Q", next_val)).decode())
|
