## Problem 032

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friol
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Joined: Mon Apr 14, 2008 8:06 pm

### Problem 032

Hello.
I think I've found the solution to problem 32, but projecteuler.net rejects it.

"Find the sum of all products whose multiplicand/multiplier/product identity can be written as a 1 through 9 pandigital. "

I think these are the products:

Removed correct solution set[/edit]

and the sum of the products is _____, but it does not seem to be the answer.
What I'm doing wrong?

Thanks

euler
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### Re: Problem 32

I've edited your post to remove the list, as it is correct. Remember, the word product means the answer you get from multiplying. You might find the hint in the problem statement helpful.

impudens simia et macrologus profundus fabulae

friol
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Joined: Mon Apr 14, 2008 8:06 pm

### Re: Problem 32

Now I've got it 8-D
Thanks.

euler
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### Re: Problem 32

You're welcome, and congrats.

impudens simia et macrologus profundus fabulae

vzhilyaev
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### Re: Problem 32

Am I getting it right that multiplicand/multiplier/product should have in total exactly nine digits?

daniel.is.fischer
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Location: Bremen, Germany

### Re: Problem 32

Yes.
Il faut respecter la montagne -- c'est pourquoi les gypa&egrave;tes sont l&agrave;.

marco6
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Joined: Sat Nov 08, 2008 5:32 pm

### Problem 32

can anyone explain me what does "pandigital" mean?
thanks

Georg
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### Re: Problem 32

Problem 41 (View Problem): We shall say that an n-digit number is pandigital if it makes use of all the digits 1 to n exactly once.

euler
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### Re: Problem 32

Good question, marco6. I hadn't realised that a definition was missing from that question. I've added the same definition from problem 41 (thanks, Georg) as an introduction to the problem.

Problem 32 (View Problem)

impudens simia et macrologus profundus fabulae

marco6
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### Re: Problem 32

Sunhill
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### Re: Problem 032

Mods: A very small typo in the last word of the first paragraph - "pandigitial".

daniel.is.fischer
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Location: Bremen, Germany

### Re: Problem 032

Thanks - fixed.
Il faut respecter la montagne -- c'est pourquoi les gypa&egrave;tes sont l&agrave;.

masteusz
Posts: 2
Joined: Fri Jan 21, 2011 12:37 pm

### Re: Problem 032

Hello,
I think that I have found correct solution but ProjectEuler rejects it so I have a question:
For example is 39 x 186 = 7254 and 186 x 39 = 7254 counted as one or two different pandigital identities?

jaap
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### Re: Problem 032

One. The problem clearly states:
HINT: Some products can be obtained in more than one way so be sure to only include it once in your sum.
Note that this is even stricter than just swapping the two factors.

masteusz
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Joined: Fri Jan 21, 2011 12:37 pm

### Re: Problem 032

Thanks, I omitted the word "once" while I was reading

jhughes
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Joined: Sun Feb 07, 2010 4:37 am

### Re: Problem 032

Could someone explain to me what this problem is referring to by "identity"? I know it's meaning in other contexts, not this one.

rayfil
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### Re: Problem 032

When you have an equal sign (=), it means that both sides must be considered identical. Thus, 39 × 186 can be considered an identity of 7254. Similarly 78 x 93, 31 x 234 and 13 x 18 x 31 would also be considered identities of 7254 among many others.
When you assume something, you risk being wrong half the time.

Spura
Posts: 8
Joined: Mon May 16, 2011 4:49 pm

### Re: Problem 032

Do we have to consider solutions with multiple multiplicands?
X * Y * Z = U

?

hk
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Location: Haren, Netherlands

### Re: Problem 032

Spura wrote:Do we have to consider solutions with multiple multiplicands?
X * Y * Z = U

?
No

Molx
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### Re: Problem 032

Spura wrote:Do we have to consider solutions with multiple multiplicands?
X * Y * Z = U

?
No, only Multiplicand * Multiplier = Product
Problem 32 (View Problem)