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@kevinyan815
Last active August 29, 2024 14:15
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function toBaseN(num, base) {
if (num === 0) {
return '0';
}
var digits = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
var len = Math.min(digits.length, base);
var result = '';
while (num > 0) {
result = digits[num % len] + result;
num = parseInt(num / len, 10);
}
return result;
}
function fromBaseN(str, base) {
if (str === null || str.length === 0) {
return 0;
}
var digits = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
var len = Math.min(digits.length, base);
var result = 0;
for (var i=0 ; i<str.length ; i++) {
var p = digits.indexOf(str[i]);
if (p < 0 || p >= base) {
return NaN;
}
result += p * Math.pow(digits.length, str.length - i - 1);
}
return result;
}
function toBase62(n) {
if (n === 0) {
return '0';
}
var digits = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
var result = '';
while (n > 0) {
result = digits[n % digits.length] + result;
n = parseInt(n / digits.length, 10);
}
return result;
}
function fromBase62(s) {
var digits = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
var result = 0;
for (var i=0 ; i<s.length ; i++) {
var p = digits.indexOf(s[i]);
if (p < 0) {
return NaN;
}
result += p * Math.pow(digits.length, s.length - i - 1);
}
return result;
}
if (!function_exists('base62_encode')) {
/**
* Convert a 10 base numeric string to a 62 base string
*
* @param int $value
* @return string
*/
function base62_encode($value)
{
return to_base($value, 62);
}
}
if (!function_exists('base62_decode')) {
/**
* Convert a string from base 62 to base 10 numeric string
*
* @param string $value
* @return int
*/
function base62_decode($value)
{
return to_base10($value, 62);
}
}
if (!function_exists('to_base')) {
/**
* Convert a numeric string from base 10 to another base.
*
* @param $value decimal string
* @param int $b base , max is 62
* @return string
*/
function to_base($value, $b = 62)
{
$base = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
$r = $value % $b;
$result = $base[$r];
$q = floor($value / $b);
while ($q) {
$r = $q % $b;
$q = floor($q / $b);
$result = $base[$r] . $result;
}
return $result;
}
}
if (!function_exists('to_base10')) {
/**
* Convert a string from a given base to base 10.
*
* @param string $value string from given base
* @param int $b base, max is 62
* @return string
*/
function to_base10($value, $b = 62)
{
$base = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
$limit = strlen($value);
$result = strpos($base, $value[0]);
for ($i = 1; $i < $limit; $i++) {
$result = $b * $result + strpos($base, $value[$i]);
}
return $result;
}
}
#!/usr/bin/python
# -*- coding=UTF-8 -*-
from __future__ import print_function, division
BASE62 = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
def encode(num, alphabet=BASE62):
"""Encode a positive number in Base X
Arguments:
- `num`: The number to encode
- `alphabet`: The alphabet to use for encoding
"""
if num == 0:
return alphabet[0]
arr = []
base = len(alphabet)
while num:
num, rem = divmod(num, base)
arr.append(alphabet[rem])
arr.reverse()
return ''.join(arr)
def decode(string, alphabet=BASE62):
"""Decode a Base X encoded string into the number
Arguments:
- `string`: The encoded string
- `alphabet`: The alphabet to use for encoding
"""
base = len(alphabet)
strlen = len(string)
num = 0
idx = 0
for char in string:
power = (strlen - (idx + 1))
num += alphabet.index(char) * (base ** power)
idx += 1
return num
if __name__ == '__main__':
print(encode(123004569870))
print(decode('2agqDFK'))
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