nothing to do with the sequence of the two rules because they are saying totally different things, the tie mean tie among the neighbors (case of multiple choices, but it does not say how the choice is derived in this statement), and obviously nothing to do with current cell having same altitude as its neighbor. Or simply, the rule is just to determine priority among the neighbor, it does not define how the conflict will arise or simply how is the flow, either "high to low" or "high to equal or lower".
On Mon, Sep 7, 2009 at 3:11 PM, jz <[email protected]> wrote: > thanks everybody. i'm still not 100% clear though, but maybe the former > rule comes prior to the latter one? > > ● For each cell, if none of its 4 neighboring cells has a lower altitude > than the current cell's, then the water does not flow, and the current cell > is called a *sink*. > ● In case of a tie, water will choose the first direction with the lowest > altitude from this list: North, West, East, South. > > that rule (colored in red) made me think that 6 in first row is 'lower' > than 6 in second row. > > so what i drew in mind was this > > → a ← > → ↑ ← > > well, maybe i've been confused. :) > > again, thanks everybody. > > > > > On Mon, Sep 7, 2009 at 2:22 PM, Hawston LLH <[email protected]> wrote: > >> i think it depend on the definition of "flow", either from (high) to (low) >> or from (high) to (equal or lower). >> based on the definition given in the question "For each cell, if none of >> its 4 neighboring cells has a lower altitude than the current cell's, then >> the water does not flow, and the current cell is called a *sink*.", the >> 1st one (from high to low) is correct. >> >> So, it doesn't matter what the reality is in real life, it all matters >> what the question really say. >> >> >> On Mon, Sep 7, 2009 at 12:51 PM, tog <[email protected]> wrote: >> >>> >>> Well I think that since 6 is a sink you can not move to the other one ... >>> You cannot move to a place being at the same height (of your current >>> position) - no slope ;) >>> >>> >>> On Mon, Sep 7, 2009 at 8:25 AM, jz<[email protected]> wrote: >>> > >>> > hey folks, good job with gcj. >>> > >>> > i couldn't understand something in prob B 'watersheds'. >>> > >>> > >>> > in following case in sample input, >>> > [2 3] >>> > 7 6 7 >>> > 7 6 7 >>> > >>> > now upper 6 and downer 6 has same altitude. >>> > >>> > So what i thought was i should follow "NORTH WEST EAST SOUTH" rule, >>> > >>> > so upper 6 must be the sink, and the basin map should be >>> > >>> > a a a >>> > a a a >>> > >>> > not >>> > a a a >>> > b b b >>> > >>> > i don't understand why BOTH 6s are sinks. 'flows' follow 'tie >>> > situations' but 'sinks' don't? >>> > >>> > >>> > >>> > > >>> > >>> >>> >>> >>> -- >>> PGP KeyID: 1024D/69B00854 subkeys.pgp.net >>> >>> http://cheztog.blogspot.com >>> >>> >>> >> >> >> > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "google-codejam" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/google-code?hl=en -~----------~----~----~----~------~----~------~--~---
