OpenEuphoria

Re: modified reverse

• Posted by Igor Kachan <kinz at peterlink.ru> Aug 05, 2001
• 508 views

Hi rforno again,

Your idea is just excellent,
I think, see new variants below:

> 
> Hi rforno,
> 
> > Rob:
> > The following modified reverse routine is simpler and, most of the
times,
> > slightly faster than the standard one. However, I noticed that the
> > comparison between the two is affected by the type of data (integer or
> not,
> > simple or compound sequence), and even it seems that the way of
> generating
> > the data (by means of a single sentence or by a loop) affects the
> resulting
> > timings. Any explanation for such a behavior?
> > 
> > global function reverse1(sequence s)
> >     integer n
> >     sequence t
> >     n = length(s)
> >     t = repeat(0,n)
> >     for i = 1 to n do
> >         t[n] = s[i]
> >         n -= 1
> >     end for
> >     return t
> > end function
> 
> rforno, Rob,
> the *very* interesting solution,
> but how about the second one,
> just inspired by rforno's the first:
> 
> sequence S
> S={{1},{2},{3},{4},{5},{6},{7},{8},{9}}
> 
> global function reverse2(sequence s)
>  integer n
>    sequence t
>     t = s
>     n = length(s)
>     for i = 1 to n do
>      t[n] = s[i]
>        n -= 1
>     end for
>    return t
> end function
> 
> ? reverse2(S)   ----     

global function reverse3(sequence s, atom n)
   sequence t
    t = s
    for i = 1 to n do
     t[n] = s[i]
       n -= 1
    end for
   return t
end function

? reverse3(S, length(S))

sequence t -- this is a single private service sequence
           -- for the different functions
           -- of the program, 
global function reverse4(sequence s, atom n)
   t = s
    for i = 1 to n do
     t[n] = s[i]
       n -= 1
    end for
   return t
end function

? reverse4(S, length(S))

Regards,
Igor Kachan
kinz at peterlink.ru