10965 - Khepel's Problem

All about problems in Volume 109. If there is a thread about your problem, please use it. If not, create one with its number in the subject.

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L I M O N
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Post by L I M O N » Thu Dec 08, 2005 3:25 pm

Moha wrote:As in problem statement, time interval for each sprinklers begin at time=0
and if a sprinkler has period p then, according to one-cycle movement, that sprinkler will pour water at it`s first direction for [0,p) and in time p it changes its direction without pouring water!
Now tell me, if a sprinkler has period 2 , then
In initial direction it pours water from time 0 to 1
In period 2, it changes it's direction without pouring any water
In the next direction it pours water from 3 to 4

Am i right ??? if not, then wt will be the correct ?

Thx in Adv.

L I M O N

tan_Yui
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Post by tan_Yui » Fri Dec 09, 2005 6:09 am

L I M O N wrote:Now tell me, if a sprinkler has period 2 , then
In initial direction it pours water from time 0 to 1
In period 2, it changes it's direction without pouring any water
In the next direction it pours water from 3 to 4

Am i right ??? if not, then wt will be the correct ?
Your idea is correct. If p==2,
pour : [0,2)
No Water : [2, 3)
pour : [3, 5)
No Water : [5, 6)
and so on.

Best regards.

fuzz_brain
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10965 - Khepel’s Problem

Post by fuzz_brain » Tue Jul 18, 2006 8:17 pm

Hello,

I have some questions concerning the problem statement.

1) Which direction is north? Is going from cell (1,1) to cell (2,1) going north? Or is it the other way around? And is going from cell (1,1) to cell (1,2) going east?
2) If the start time is 10 and the end time is 10, do I have to consider the interval [10,11) or is it the interval [10,10]?

mf
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Post by mf » Tue Jul 18, 2006 8:30 pm

1) North is up and west is left. as with most maps.
2) It's from the beginning of 10th second till the end of 10th second, so [10, 11).

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