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Posted: **Sun Feb 08, 2004 12:16 pm**

by **sohel**

Hi Mahmud,

Your output does not seem to be right.

Example:

()*()

this should give a negative result----- but your one doesn't;

the corresponding closing of the first should be the last.

Hope it helps.

### Not Specified

Posted: **Tue Feb 10, 2004 11:40 am**

by **Mahmud776**

**Hi Sohel,**
I think the above sample inputs and outputs are not wrong as I got accepted with this inputs and outputs. You said,

()*()

this should give a negative result----- but your one doesn't;

the corresponding closing of the first should be the last.

But, I think, here () is followed by a separate character * and this sequence is followed by another ().As () is a correct sequence so, I think, ()*() should give positive answer. After all I got accepted in this way.

*Mahmud*

Posted: **Fri Mar 05, 2004 4:07 pm**

by **angga888**

Hi,

I'm getting WA for this problem.

Can someone explain me why these 2 inputs give different outputs.

((**)()a+b)[(a){a+n}](*

((**)()a+b)[(a){a+n}](

And I'm not sure what this statement means?

"If the expression is not properly nested your program should determine the position of the offending bracket, that is the length of the shortest prefix of the expression that can not be extended to a properly nested expression."

Thanx,

angga888

### don't think so

Posted: **Sun Mar 07, 2004 6:59 am**

by **sohel**

Hi again,

((**)()a+b)[(a){a+n}](*

((**)()a+b)[(a){a+n}](

How do you know these two inputs give two different outputs---

my AC program gives the same output..... very strange.

And I'm not sure what this statement means?

"If the expression is not properly nested your program should determine the position of the offending bracket, that is the length of the shortest prefix of the expression that can not be extended to a properly nested expression."

this is actually the first bracket (from left) that is out of position.

eg. ())[]9()909

it will be impossible for a valid combination to emerge after the third bracket ..).. therefore this particular one is the offending one.

Hope it helps.

### Not specified

Posted: **Sun Mar 07, 2004 2:10 pm**

by **Mahmud776**

Hi:

Sohel is correct.

Here, '(*' has to be considered as different characters

as '(*' is not completed and they are the last two characters in

that sequence.

((**)()a+b)[(a){a+n}](*

Posted: **Sun Mar 07, 2004 2:39 pm**

by **angga888**

Hi,

How do you know these two inputs give two different outputs---

my AC program gives the same output..... very strange.

I look at the first post in this topic and I've got AC now.

Thanks for your reply.

Regards,

angga888

Posted: **Sun Jun 20, 2004 4:34 pm**

by **Rajib**

**Which one is wrong, Problem description or the sample input ????**

Posted: **Sun Jun 20, 2004 4:36 pm**

by **Rajib**

When I get a WA in the problem, then I check out some help for me and I test the sample input given by

**Mahmud776**. I was mad with his sample input because I fail to match with his output. But those are output from his AC code. So I was not confident to say his output was wrong.

But finally understanding the problem properly I get AC and find that his output was wrong. I think

**Judge Data** is not strong enough to test the solution of problem. Though I think the problem was little confusing because it ask for the minimum prefix which can't extended as correct one.

For example:

()()(a+b)(

Output for it: NO 11

But that expration can be extended as correct one like; ()()(a+b)(

**)**
So output should be 'YES' rather 'NO 11'

### 551

Posted: **Sun Oct 17, 2004 8:38 pm**

by **Emilio**

Hi:

Can anyone help me?

I only need the outputs for this inputs, or others inputs/outputs with some special cases.

Thanks!

Input:

(*adf(y)(*

(*adf(y)(

(a*)

)()

*)()

ads()asdf

(***)

(**

({{]}]

(**){*{]}]

<><

<sgf(sfg[sfg{sfg(*sfgsdfg*)dhj}]dfh)>

<sgf(sfg[sfg{sfg(*sfgsdfg*)dhj}]dfh)><

<sgf(sfg[sfg{sfg(*sfgsdfg*)dhj}]dfh)>(*

[**

((((())

(*(*(*(**)*)

(**********(

(*a++(*)

(*a{+}*)

(*)

(**)

((**))

((()))

{}{}{}{}{}{}{}{}{

{{{}[()((**))][][]}}

(())))

(***)

{*(())(()*)*}

{adfadf[adfadf(adfa(*adfadf*)adfaf)(*afdsf*)]adfadf}

(AADFASDFADSF)

Posted: **Thu Oct 21, 2004 7:53 am**

by **jagadish**

No 9

No 9

No 3

No 1

No 1

Yes

Yes

No 3

No 4

No 6

No 4

Yes

No 37

No 37

No 4

No 8

No 7

No 12

No 6

Yes

No 2

Yes

Yes

Yes

No 18

Yes

No 5

Yes

No 10

Yes

Yes

Posted: **Fri Oct 22, 2004 6:54 am**

by **Emilio**

Thanks very much jagadish!

I got AC to the first!

I only had a small mistake!

Thanks!

Posted: **Fri Apr 08, 2005 4:28 am**

by **Raiyan Kamal**

Dear Mahmud776,

one of the sample cases you have posted here is wrong. for the input

you said the output is

which is wrong. my AC code gives output

I guess this is a silly typo. Again, for the case

I considered the last '(*' as one symbol and that is what one is supposed to for all the cases in this problem.

Posted: **Mon May 30, 2005 3:38 pm**

by **Sedefcho**

Apparently the output logic of this problem is quite arguable.

I tend to agree with

Rajib's theory that for

cases like

the output should be

because strings of this kind can be extended so that they

represents a valid bracketing ( a valid expression ).

I mean they have no prefix for which no extension is possible.

Anyway. Apparently there's some mess about this problem.

But I doubt the Judge's tests follow this

logic (

Rajib's theory ).

I found another thread where there's sufficient I/O.

http://online-judge.uva.es/board/viewtopic.php?t=6724
jagadish has posted some output there which

is quite close to mine although it differs in some cases.

We differ in the following test cases:

input

my output

his output

It would be nice if someone having ACC program could

verify and say which one of these outputs is correct. I hope

he/she won't come up with a new theory about

how a correct answer should look like

Posted: **Mon May 30, 2005 5:31 pm**

by **Sedefcho**

Can someone explain these outputs

Output

for the following

Input

My WA program currently prints

Output

for that sample input.

Could someone explain if/why my output is wrong

and if/why the first output ( from

jagadish ) is OK ?

These are the only test cases in which my Output differs

from

jagadish's Output for his sample Input ( see above ).

I have made also a post in

http://online-judge.uva.es/board/viewtopic.php?t=4897
but that thread is even more confusing. The theory of

Rajib
seems reasonable to me but when I follow it the Judge still

gives me WA. Although I would say this interpretation is the

most correct one ( logically ).

Thanks in advance.

Any help is welcome.

Posted: **Mon May 30, 2005 8:43 pm**

by **Raiyan Kamal**

My output is same as Jagadish.