From: Shannon Fang <xrfang@...>
Date: 2006-04-18T12:18:17+09:00
Subject: Re: a simple RSA

Thanks a lot, this works fine.

BTW, another related question: while I ruby code, I can write a long string 
like: (without using heredoc)

str = "this is very long line 1" +
        "this is line 2"

but if I write a number:

num = 0x1234132410987094750245.....

And the number is very long (an RSA key), how can I wrap the line? it seems 
that I cannot use a "\" by the end of line...

Thanks!
Shannon

>From: "Sergey" <gm.vlkv@gmail.com>
>Reply-To: ruby-talk@ruby-lang.org
>To: ruby-talk@ruby-lang.org (ruby-talk ML)
>Subject: Re: a simple RSA
>Date: Tue, 18 Apr 2006 06:19:07 +0900
>
>Please see attached:
>- samples with unpack/inject and each_byte use in str_to_num;
>  each_byte is faster;
>- num_to_str without use of formatting;
>- unit test stuff and
>- benchmark code
>
>hope these help
>regards
>Sergey
>
>----- Original Message ----- On Monday, April 17, 2006 2:03 PM, Shannon 
>Fang wrote:
>>Hi All,
>>
>>I tried to implement a simple RSA crypto for my work. It seems all works 
>>fine, except that I am not satisfied with the code I wrote below:
>>
>>def str_to_num(s)
>>  h = '0x'
>>  (0...s.length).each do |i|
>>    h += "%02x" % s[i]
>>  end
>>  eval(h)
>>end
>>
>>def num_to_str(n)
>>  s = ''
>>  while n > 0 do
>>    s = "%c" % (n & 0xFF) + s
>>    n = n >> 8
>>  end
>>  s
>>end
>>
>>These 2 functions convert string to bignum and vise-versa. It works, but I 
>>feel there should be better (faster) way to do this.
>>
>>Could anyone point the way out?
>>
>>Thanks!
>>Shannon


><< tStrToNum.rb >>