Martin DeMello
8/22/2006 9:34:00 AM
On 8/22/06, John Carter <john.carter@tait.co.nz> wrote:
> Here is my very very silly one liner for the day....
>
> ruby -e '100.times{|n| a,b=n.divmod 10;10.times{|c|;d=c*10+a;next unless
> d!=0&&n%d==0&&b==c*n/d;printf "%02d/%02d=%d\n",n,d,n/d}}'
> 00/10=0
> 00/20=0
> 00/30=0
> 00/40=0
> 00/50=0
> 00/60=0
> 00/70=0
> 00/80=0
> 00/90=0
> 10/01=10
> 11/11=1
> 20/02=10
> 22/22=1
> 30/03=10
> 33/33=1
> 40/04=10
> 44/44=1
> 50/05=10
> 55/55=1
> 60/06=10
> 64/16=4
> 66/66=1
> 70/07=10
> 77/77=1
> 80/08=10
> 88/88=1
> 90/09=10
> 95/19=5
> 98/49=2
> 99/99=1
Took me a good minute to figure out what you were doing there :) Cute,
though I submit that
n/d = 10 and n/d = 1 are artistically unsatisfying, particularly the
former. Plus you miss a nice case...
ruby -rrational -e '100.times{|n| a,b=n.divmod
10;10.times{|c|d=c*10+a;next unless (n!=d) && (b*d!=0) &&
(b*d==c*n);printf "%02d/%02d=#{Rational(n,d)}\n",n,d}}'
64/16=4
65/26=5/2
95/19=5
98/49=2
martin