From: "David A. Black" <dblack@...>
Date: 2008-05-09T05:12:27+09:00
Subject: Re: scramble sentence, how to better program?

Hi --

On Fri, 9 May 2008, globalrev wrote:

> i have written a program that takes a sentence as input and outputs
> the sentence with the words rearranged.
> it is probably inefficient and can probably be done with less code.
> it is also nondeterministic(  while (inList(temp,scr))  could go on
> for a long time if the user is unlucky) and im not sure how to get
> around that or if it is even possible.
> also, if there is 2 identical words in the sentence, lets say "the" is
> in there twice, it will loop forever. i could do
> .uniq in the beginning but lets say i want both "the" to be in there.
> i have to write some if duplicate then ok up to nbrofduplicates. is
> there an easy way to do this?
>
> #scrambler
> puts "Enter a sentence: "
> sentence = gets
> list = sentence.split()
> scr = []
>
> def inList(aword,alist)
> 	inl=false
> 	for i in (0..alist.length()-1)
> 		if alist[i] == aword
> 			inl=true
> 		end
> 	end
> 	return inl
> end

Much easier:

   def in_list?(aword, alist)
     alist.include?(word)
   end

which means you don't really need your own method; you can just call
include? on your list.

> for x in (0..list.length()-1)
> 	temp = list[rand(list.length())]
> 	while (inList(temp,scr))
> 		temp = list[rand(list.length())]
> 	end
> 	scr = scr + temp.split()
> end

Please lose the ()'s. They don't do anything or add any information;
they're just visual clutter. Meanwhile, see below....

> puts "Scrambled: "
> puts scr

In general, you're working much too hard :-) Let Ruby do it for you:

   print "Enter a sentence: "
   puts gets.split.sort_by { rand }.join(" ")


David

-- 
Rails training from David A. Black and Ruby Power and Light:
   INTRO TO RAILS         June 9-12            Berlin
   ADVANCING WITH RAILS   June 16-19           Berlin
   INTRO TO RAILS         June 24-27           London (Skills Matter)
See http://www.rubypal.com for details and updates!