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Re: About python while statement and pop()

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2014年6月12日木曜日 14時43分42秒 UTC+9 Steven D'Aprano:
> On Wed, 11 Jun 2014 21:56:06 -0700, hito koto wrote:
> 
> 
> 
> > I want to use while statement,
> 
> > 
> 
> > for example:
> 
> >>>> def foo(x):
> 
> > ...     y = []
> 
> > ...     while x !=[]:
> 
> > ...         y.append(x.pop())
> 
> > ...     return y
> 
> > ...
> 
> >>>> print foo(a)
> 
> > [[10], [5, 6, 7, 8, 9], [1, 2, 3, 4]]
> 
> >>>> a
> 
> > []   but this is empty
> 
> >>>> so,I want to leave a number of previous (a = [[1, 2, 3, 4],[5, 6, 7,
> 
> >>>> 8, 9],[10]])
> 
> 
> 
> 
> 
> I wouldn't use a while statement. The easy way is:
> 
> 
> 
> py> a = [[1, 2, 3, 4],[5, 6, 7, 8, 9],[10]]
> 
> py> y = a[::-1]
> 
> py> print y
> 
> [[10], [5, 6, 7, 8, 9], [1, 2, 3, 4]]
> 
> py> print a
> 
> [[1, 2, 3, 4], [5, 6, 7, 8, 9], [10]]
> 
> 
> 
> If you MUST use a while loop, then you need something like this:
> 
> 
> 
> 
> 
> def foo(x):
> 
>     y = []
> 
>     index = 0
> 
>     while index < len(x):
> 
>         y.append(x[i])
> 
>         i += 1
> 
>     return y
> 
> 
> 
> 
> 
> This does not copy in reverse order. To make it copy in reverse order, 
> 
> index should start at len(x) - 1 and end at 0.
> 
> 
> 
> 
> 
> 
> 
> -- 
> 
> Steven

Hi, Steven:
Thanks,

My goal is to be able to in many ways python

Sorry, I was mistake,
I want to leave a number of previous (a = [[10], [9, 8, 7, 6, 5], [4, 3, 2, 1]] )

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About python while statement and pop() hito koto <hitokoto2014@gmail.com> - 2014-06-11 20:12 -0700
  Re:About python while statement and pop() Dave Angel <davea@davea.name> - 2014-06-11 22:34 -0500
  Re: About python while statement and pop() Vincent Vande Vyvre <vincent.vandevyvre@swing.be> - 2014-06-12 05:40 +0200
  Re: About python while statement and pop() Chris Angelico <rosuav@gmail.com> - 2014-06-12 13:58 +1000
    Re: About python while statement and pop() hito koto <hitokoto2014@gmail.com> - 2014-06-11 21:56 -0700
      Re: About python while statement and pop() Chris Angelico <rosuav@gmail.com> - 2014-06-12 15:08 +1000
      Re: About python while statement and pop() Steven D'Aprano <steve@pearwood.info> - 2014-06-12 05:43 +0000
        Re: About python while statement and pop() hito koto <hitokoto2014@gmail.com> - 2014-06-11 23:06 -0700
        Re: About python while statement and pop() hito koto <hitokoto2014@gmail.com> - 2014-06-12 00:13 -0700
        Re: About python while statement and pop() hito koto <hitokoto2014@gmail.com> - 2014-06-12 02:51 -0700
  Re: About python while statement and pop() Mark H Harris <harrismh777@gmail.com> - 2014-06-12 11:41 -0500
  Re: About python while statement and pop() Mark H Harris <harrismh777@gmail.com> - 2014-06-12 11:49 -0500
    Re: About python while statement and pop() Marko Rauhamaa <marko@pacujo.net> - 2014-06-12 19:55 +0300
      Re: About python while statement and pop() Mark H Harris <harrismh777@gmail.com> - 2014-06-12 12:07 -0500
    Re: About python while statement and pop() Chris Angelico <rosuav@gmail.com> - 2014-06-13 02:57 +1000
      Re: About python while statement and pop() Mark H Harris <harrismh777@gmail.com> - 2014-06-12 12:10 -0500
      Re: About python while statement and pop() Mark H Harris <harrismh777@gmail.com> - 2014-06-12 12:16 -0500
        Re: About python while statement and pop() wxjmfauth@gmail.com - 2014-06-12 11:37 -0700

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