[#406419] Recursion with Hash — Love U Ruby <lists@...>

h = {a: {b: {c: 23}}}

14 messages 2013/04/01

[#406465] Exclusively for Rubyists, a community on Facebook — "senthil k." <lists@...>

I was surprised to know that there is no community for Ruby Programming

12 messages 2013/04/03
[#406467] Re: Exclusively for Rubyists, a community on Facebook — Marc Heiler <lists@...> 2013/04/04

Thing is, some people do not use Facebook and never will.

[#406528] Role of bundler in creating and installing a gem — Jon Cairns <lists@...>

Hi fellow rubyists,

11 messages 2013/04/05

[#406555] How do you know what the main file in Ruby Projects is? — peteV <pete0verse@...>

Hi Ruby people,

18 messages 2013/04/05
[#406558] Re: How do you know what the main file in Ruby Projects is? — "Carlo E. Prelz" <fluido@...> 2013/04/05

Subject: How do you know what the main file in Ruby Projects is?

[#406560] Re: How do you know what the main file in Ruby Projects is? — Hans Mackowiak <lists@...> 2013/04/05

Carlo E. Prelz wrote in post #1104616:

[#406562] Re: How do you know what the main file in Ruby Projects is? — "D. Deryl Downey" <me@...> 2013/04/05

Actually its not wrong. What it does is explicitly state which ruby

[#406563] Re: How do you know what the main file in Ruby Projects is? — Matt Lawrence <matt@...> 2013/04/05

On Sat, 6 Apr 2013, D. Deryl Downey wrote:

[#406564] Re: How do you know what the main file in Ruby Projects is? — Hans Mackowiak <lists@...> 2013/04/05

Matt Lawrence wrote in post #1104625:

[#406566] Re: How do you know what the main file in Ruby Projects is? — Matt Lawrence <matt@...> 2013/04/05

On Sat, 6 Apr 2013, Hans Mackowiak wrote:

[#406570] Re: How do you know what the main file in Ruby Projects is? — Matthew Mongeau <halogenandtoast@...> 2013/04/05

I'm interested in the issue with using env, but I find you explanation a but=

[#406600] Mapping string data ptr to buffer in ffi — se gm <lists@...>

I'm trying to implement some "shared memory" in Ruby, but I'm not sure

20 messages 2013/04/08

[#406683] confusion with Struct class — Love U Ruby <lists@...>

I went to there - http://www.ruby-doc.org/core-2.0/Struct.html but the

29 messages 2013/04/11
[#406694] Re: confusion with Struct class — Love U Ruby <lists@...> 2013/04/11

Why does every time the has value getting changed,while the instance

[#406762] Why does #content method in nokogiri not printing the full text? — Love U Ruby <lists@...>

Here is the documentation: http://www.rubydoc.info/gems/nokogiri/frames

19 messages 2013/04/14
[#406764] Re: Why does #content method in nokogiri not printing the full text? — tamouse mailing lists <tamouse.lists@...> 2013/04/14

On Sun, Apr 14, 2013 at 11:19 AM, Love U Ruby <lists@ruby-forum.com> wrote:

[#406874] Input: sentence Modify: words Output: modified sentence — Philip Parker <lists@...>

I am new to Ruby. This is a programming interview question to use any

11 messages 2013/04/19

[#406912] Tap method : good or bad practice ? — Sébastien Durand <lists@...>

Hi all !

18 messages 2013/04/21

[#406936] BEGINNER -CLASS QUERY — shaik farooq <lists@...>

HEY as we know that the object conatins the instance variables that are

22 messages 2013/04/22

[#406966] copying files syntax with FileUtils.rb (grr.) — Thomas Luedeke <lists@...>

In my Ruby scripting, there is probably no greater and chronic source of

10 messages 2013/04/23

[#406969] what is the $- magic global? — Matthew Kerwin <lists@...>

I've been searching for the past hour or so, including manually stepping

13 messages 2013/04/24

[#407059] New Rexx like data structure — Peter Hickman <peterhickman386@...>

This is just something that I have been playing with for some time but I

11 messages 2013/04/29

[#407070] writing lines to a file — peteV <pete0verse@...>

I have a text file with on every line a magic card number and such info

13 messages 2013/04/29

Looking for a more elegant solution.

From: Shaw xx <lists@...>
Date: 2013-04-12 15:03:38 UTC
List: ruby-talk #406739
I'm new to ruby and working on such a problem:

There n numbered letters and n numbered envelops.  The letter x can't be
put into the envelop x. What I want is to print out all the possible
cases.

[letter(x1), letter(x2), ... , letter(xn)]
      |            |                  |
 envelop1, envelop2, ... ,  envelop n

The index of Array + 1 ---> the number of the envelop

The element of Array ---> the number of the letter

Input:      n = 3.
Output:    [1, 3, 2], [2, 3, 1]

Input:     n = 4.
Output:   [2, 1, 4, 3], [2, 3, 4, 1], [2, 4, 1, 3], [3, 1, 4, 2],
          [3, 4, 1, 2], [3, 4, 2, 1], [4, 1, 2, 3], [4, 3, 1, 2],
          [4, 3, 2, 1]

Here is my code:
-----------------------
$nums = []

def f( already, n, times )
  if n > times
    $nums << already.dup
    return
  else
    1.upto(times) do |i|
      next if ((already.include? i) || n == i)
      already << i
      f( already, n+1, times )
      already.pop
    end
  end
end
------------------------

Sorry for my poor English. Thank you very much.

-- 
Posted via http://www.ruby-forum.com/.

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