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        riddles >> easy >> A few match puzzles
        
(Message started by: BNC on Jan 26^th, 2003, 6:44am)

Title: A few match puzzles
Post by BNC on Jan 26^th, 2003, 6:44am

Starting all of the following with this initial state (12 matches)

Code:

- -
| | |
- -
| | |
- -

solve:

1. Remove two matches to get two squares -- one larger than the other.

2. Move 3 matched to get 3 identical squares.

3. Move 4 matched to get 3 identical squares.

4. Move 2 matches to get 7 (non-identical) squares.
hint: [hide]you may place one match over another[/hide]

5. Move 4 matches to get 10 (non-identical) squares.

6. Move 8 matches to get 6 identical squares.

[edit]
Edited to fix error (sorry...) on #5 -- changed number of required squares to 10.
[/edit]

Title: Re: A few match puzzles
Post by Misha on Jan 26^th, 2003, 6:21pm

1. Remove 2 matches for 2 squares one larger than other:
__ __
|__| |
|__ __|

2. Move 3 matches for 3 identical squares:

3. Move 4 matched to get 3 identical squares.

  _
|_|_
  |_|_
    |_|

4. Move 2 matches to get 7 (non-identical) squares.
hint: you may place one match over another
_ _
|+| |
- -
|_| (well you get the idea)

5. Move 4 matches to get 7 (non-identical) squares.

6. Move 8 matches to get 6 identical squares.

Gave up on the rest

[edit by Icarus to fix formatting on #3]

Title: Re: A few match puzzles
Post by BNC on Jan 27^th, 2003, 4:37am

Had an error on number 5 (sorry).
Edited to change required number of squares to 10.

Title: Re: A few match puzzles
Post by Garzahd on Jan 27^th, 2003, 11:01am

1) See Misha's answer
2) Choose 3 matches at random and turn them upside down in place
3) Choose 4 matches at random and turn them upside down in place
4) See Misha's answer
5) Pull the two matches closest to the upper left and lower right corners, then put two matches in a + sign in the middle of each of the two remaining squares
6) Same as #5, then choose 4 matches at random and turn them upside down in place

Title: Re: A few match puzzles
Post by bobcat on Mar 4^th, 2004, 6:45pm

A nicer solution for #3 that uses all the matches would be

_
|_| _
|_| _
|_|

For #2 and #6 there must be better solution that uses all the matches and changes their position rather than lifting them and replacing them where they were (although I have not discovered it yet).

Title: Re: A few match puzzles
Post by bobcat on Mar 4^th, 2004, 6:48pm

My apologies, Misha. Looks like our artwork was the same but did not work out :( (Should be three squares on a diagonal).

Title: Re: A few match puzzles
Post by bobcat on Mar 4^th, 2004, 7:37pm

For #6, make a cube.

Title: Re: A few match puzzles
Post by Icarus on Mar 5^th, 2004, 7:50pm

A trick for fixing the spacing: When you first post, for some reason YaBB has the weird idea that it absolutely must collapse any occurences of a set number of spaces in a row (I think it is 7) down to a single space. The only way I know to stop this is to use the "code" tag. Not even the "preformatted text" tag will change YaBB's mind on this.

But, when you modify a post, it skips this "collapse the spaces" step. So you can post, immediately modify the post, and repost again without making any changes. Then it will stop collapsing the spaces. I have done this to both your and Misha's posts, so your diagonal diagrams now show as intended.

Title: Re: A few match puzzles
Post by bobcat on Mar 7^th, 2004, 2:59pm

Thanks Icarus. I enjoy puzzles and riddles but computers are not my strength :(. I am getting there though...

Title: Re: A few match puzzles
Post by Icarus on Mar 8^th, 2004, 9:32pm

This quirk isn't anyone's strength. It's just one of those tricks that people stumble across eventually, then share around. There was no reason to expect that YaBB should work this way. An intelligent design wouldn't collapse the spaces for the original posts either.

Title: Re: A few match puzzles
Post by MMS85249 on May 21^st, 2004, 1:45pm

Did anyone ever post an answer to "Move 3 matched to get 3 identical squares"?

Title: Re: A few match puzzles
Post by Three Hands on May 21^st, 2004, 3:21pm

Garzahd did, but I think the correct answer is to take two matches from one corner of the big square and one from the opposite corner of the big square (external, rather than internal matches) and then put these three matches in place to form a square with the originally external match in the corner you took the third match from. You should end up with a kind of zig-zag formation for the squares - one line of three matches with one square below in the middle and two above on the ends.

(maybe I should figure out how to draw...)

Title: Re: A few match puzzles
Post by grimbal on May 22^nd, 2004, 5:24pm

on 05/21/04 at 13:45:25, MMS85249 wrote:

Did anyone ever post an answer to "Move 3 matched to get 3 identical squares"?

2.-- -- | | | | -- -- -- | | --

Title: Re: A few match puzzles
Post by Three Hands on May 23^rd, 2004, 3:40am

Thanks Grimbal - that's pretty much what I was trying to describe :)

Title: Re: A few match puzzles
Post by grimbal on May 23^rd, 2004, 11:11am

A picture is worth a hundred words.
(92 if you don't count the "(maybe I should ...)" at the end).

Title: Re: A few match puzzles
Post by Three Hands on May 23^rd, 2004, 11:15am

:D So it is. Guess that proves I'm reasonably good at being concise, given the usually accepted conversion rate of words to pictures...

I suppose it counts as rather sad that I then decided to check that statement...

Title: Re: A few match puzzles
Post by Sir Col on May 24^th, 2004, 6:14am

on 03/05/04 at 19:50:17, Icarus wrote:

A trick for fixing the spacing...

The reason for the "glitch" is quite complicated. Firstly, HTML (the encoded characters in your browser window) does not support multiple spaces. Although the spaces still exist in the document, the browser ignores them. So the text, "Hello World", embedded in a document would display the same as "Hello World" in a normal HTML document. However, yaBB goes some of the way to modify this by converting spaces in a post to non-breaking spaces (which do display). A HTML programmer would need to artificially inserting " " as necessary (each displays on the screen as a space and you can concatenate as many as you wish). However, it seems that the yaBB software is limited to converting no more than 7 consecutive characters.

A potential work around is to use the actual non-breaking character in your post via its ASCII code. For example, holding down ALT and typing 0065 on the numeric key pad would display "A" (the zeroes at the front are not necessary in this case, but to be consistent with the following I included them). The non-breaking space is an extended ASCII character (beyond 127), so to use it, hold ALT and type 0160.

Alas, yaBB is smart and parses even these characters! :(

So Icarus' clever trick is the best solution. How he discovered it, I do not know? Bravo!

Title: Re: A few match puzzles
Post by Icarus on May 24^th, 2004, 4:53pm

Even in HTML you can get the correct spacing using the preformatted text tags <pre> </pre>. Alas, YaBB's tags are not so well-behaved.

As to how I discovered it, it was by reading someone else's post to this effect long ago!

Title: Re: A few match puzzles
Post by Barukh on May 27^th, 2004, 3:41am

Let me go back to the origin of this thread. ;)

The solutions to BNC's #2 and #3 show the way to arrange 12 matches so that they enclose exactly 3 square "match units".

Find at least two other arrangements of that kind. Both should enclose a single area.

Title: Re: A few match puzzles
Post by grimbal on May 27^th, 2004, 5:32pm

Any shape? For example: _ |\/\/_| \/\/where the \/\/ are at angles 60°
or
./\./\. | ./\| |/\|again, the /\ are 60° angles.