Re: count zeros in a number
- To: mathgroup at smc.vnet.net
- Subject: [mg121800] Re: count zeros in a number
- From: DrMajorBob <btreat1 at austin.rr.com>
- Date: Mon, 3 Oct 2011 04:21:11 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <201110020636.CAA28027@smc.vnet.net>
- Reply-to: drmajorbob at yahoo.com
n = 24^24*55^55
6998705566601499878519159087153235987310926417579055430641039765858300\
72320000000000000000000000000000000000000000000000000000000
IntegerDigits[n] /. {__, zeroes : 0 ..} :> Length@{zeroes}
55
The more complicated version:
IntegerDigits[n] /. {__, zeroes : Longest[0 ..]} :> Length@{zeroes}
55
isn't necessary, because __ is taken to mean Shortest[__] by default.
Bobby
On Sun, 02 Oct 2011 01:36:47 -0500, dimitris <dimmechan at yahoo.com> wrote:
> Hello.
>
> Consider e.g. the number 24^24*55^55.
> This number ends with exactly 55 zeros as the following demonstrate
>
> In[201]:= Mod[24^24*55^55, 10^55]
> Mod[24^24*55^55, 10^56]
>
> Out[201]= 0
> Out[202]= 20000000000000000000000000000000000000000000000000000000
>
>
> What I want now is a way to count the zeros that a number ends without
> knowing in advance this number of zeros like in the above example.
>
> Thanks in advance.
> Dimitris
>
--
DrMajorBob at yahoo.com
- References:
- count zeros in a number
- From: dimitris <dimmechan@yahoo.com>
- count zeros in a number