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Re: What's the best way to make a cross string set?

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On 7/27/2017 3:12 PM, Eric Douglas wrote:
> I have a variable number of lists of values, as in
> ArrayList list1 = new ArrayList()
> ArrayList list2 = new ArrayList()
> list2.add("a")
> list2.add("b")
> list2.add("c")
> list1.add(list2)
> ArrayList list3 = new ArrayList()
> list3.add("1")
> list3.add("2")
> list3.add("3")
> list1.add(list3)
> ArrayList list4 = new ArrayList()
> list4.add("fg")
> list4.add("hj")
> list4.add("kl")
> list1.add(list4)
> 
> Now I want to print only the complete set, as in
> a1fg
> b1fg
> c1fg
> a2fg
> b2fg
> c2fg
> a3fg
> b3fg
> c3fg
> a1hj
> b1hj
> ...

     If by "complete set" you mean "the Cartesian product of all the
lists contained in list1," where list1 might hold N embedded lists
(more generally, Collections) instead of just three, I'd suggest a
recursive solution along the lines of:

	void tuples(List bigList, int which, String soFar) {
	    if (which < bigList.size()) {
	       for (Object item : bigList.get(which)) {
	           tuples(bigList, which + 1, soFar + item);
	       }
	    } else {
	        System.out.println(soFar);
	    }
	}
	...
	tuples(list1, 0, "");

     If that's not what you want, please explain "complete set"
more fully.

-- 
esosman@comcast-dot-net.invalid
Twelve hundred seventy-three days to go.

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What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-27 12:12 -0700
  Re: What's the best way to make a cross string set? Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2017-07-27 14:38 -0500
    Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-27 12:49 -0700
  Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-07-27 15:49 -0400
    Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-27 12:55 -0700
    Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-27 13:22 -0700
      Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-27 13:30 -0700
      Re: What's the best way to make a cross string set? Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2017-07-27 15:34 -0500
      Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-07-27 18:27 -0400
        Re: What's the best way to make a cross string set? lewbloch@gmail.com - 2017-07-28 18:51 -0700
    Re: What's the best way to make a cross string set? v_borchert@despammed.com (Volker Borchert) - 2017-07-29 06:03 +0000
  Re: What's the best way to make a cross string set? v_borchert@despammed.com (Volker Borchert) - 2017-07-28 18:19 +0000
    Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-28 13:28 -0700
      Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-07-28 17:20 -0400
        Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-31 05:24 -0700
          Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-07-31 12:01 -0400
            Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-07-31 10:58 -0700
          Re: What's the best way to make a cross string set? Sebastian <nowhere@nirvana.org> - 2017-07-31 18:13 +0200
          Re: What's the best way to make a cross string set? lewbloch@gmail.com - 2017-07-31 09:24 -0700
          Re: What's the best way to make a cross string set? Arne Vajhøj <arne@vajhoej.dk> - 2017-07-31 19:24 -0400
        Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-01 06:36 -0700
          Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-08-01 10:58 -0400
            Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-01 08:09 -0700
              Re: What's the best way to make a cross string set? lewbloch@gmail.com - 2017-08-01 09:39 -0700
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-01 10:18 -0700
                Re: What's the best way to make a cross string set? Andreas Leitgeb <avl@logic.at> - 2017-08-02 09:22 +0000
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-02 05:13 -0700
                Re: What's the best way to make a cross string set? Andreas Leitgeb <avl@logic.at> - 2017-08-03 14:33 +0000
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-03 08:51 -0700
                Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-08-03 12:20 -0400
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-03 10:15 -0700
                Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-08-03 13:42 -0400
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-03 11:17 -0700
                Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-08-05 16:08 -0400
                Re: What's the best way to make a cross string set? Martin Gregorie <martin@address-in-sig.invalid> - 2017-08-05 20:31 +0000
                Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-08-05 17:25 -0400
                Re: What's the best way to make a cross string set? Martin Gregorie <martin@address-in-sig.invalid> - 2017-08-05 22:11 +0000
                Re: What's the best way to make a cross string set? Sebastian <nowhere@nirvana.org> - 2017-08-06 18:13 +0200
                Re: What's the best way to make a cross string set? Eric Douglas <e.d.programmer@gmail.com> - 2017-08-02 12:56 -0700
  Re: What's the best way to make a cross string set? Eric Sosman <esosman@comcast-dot-net.invalid> - 2017-07-29 16:55 -0400
  Re: What's the best way to make a cross string set? Sebastian <nowhere@nirvana.org> - 2017-07-29 23:56 +0200

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