基数62转换

import string

# 基数62字符集
BASE62_CHARS = string.ascii_letters + string.digits

def encode_base62(num):
    if num == 0:
        return BASE62_CHARS[0]
    arr = []
    base = len(BASE62_CHARS)
    while num:
        num, rem = divmod(num, base)
        arr.append(BASE62_CHARS[rem])
    arr.reverse()
    return ''.join(arr)

def decode_base62(s):
    num = 0
    base = len(BASE62_CHARS)
    for char in s:
        num = num * base + BASE62_CHARS.index(char)
    return num

# 示例
encoded = encode_base62(123456789)
print(f"Encoded: {encoded}")  # 输出: Encoded: 1Ee5k

decoded = decode_base62(encoded)
print(f"Decoded: {decoded}")  # 输出: Decoded: 123456789