I spent some time trying to figure out an example from your answer. I came to the conclusion that it has a mistake. "Allow" has base 26, but not 25.

Not sure what do you mean by not working? it seems to be working

You have to calculate the remainders, not the quotients.

10 % 13 = 10
100 % 13 = 9
1000 % 13 = 12
10000 % 13 = 3
... and so on until you see the cycle

Divide some power of 10 by hand and you will see...

Nobody's going to change the requirements after 5k solutions.

Given two set of digits (source and destination) and one string containg a "number" (this "number" can contain alphanumerical "digits"). Change the base or radix of this given "number" to other bases using the digits of the destination base.

Example (Converting the number "hello" in base "allow" to base 10):

In base "allow" we have the digits "a,b,c,d,...,z"; the "a" is the number 0 in base 10, meanwhile z is number 25 in base 10.

We take the 'h' and multiply it decimal value by pow(25, 4). 25 is the base number (We only have 25 digits, and 4 is the "position" of the digit in the number)
now with e, and l, and so on. Now we sum all the values of each digits and now we have a number in base 10, which is: 3276872

Remember that each base uses different digits.

900 and 500 have the same number of digits, the first of them is 900, not 8.

Issue is also with Java unit tests, years:
1001, 858, 986 and some others do not work well.

If you mean the spaces around the curly braces, I use it as suggested in the Ruby styleguide

Cheers

Hi, modified the description and the tests in Ruby to avoid this "ISSUE". Regards, suic

Have you read the note and/or the post below?