Algorithm Geeks Google Group

Re: [algogeeks] Dominoes Covering

aryansmit3...@gmail.com (sharad kumar) — Fri, 20 Nov 2009 14:11:07 UT

are u asking about dancing links as told in toacp for exact cover
problem.isnt this an NP complete according to CLRS

Dominoes Covering

masterrays...@gmail.com (ShingRay) — Fri, 20 Nov 2009 13:12:31 UT

Hi, here is the problem:

Given a m*n chessboard, determine if it is possible to use p*q
dominoes completely cover it? Domnoes cannot cross each other.

Thanks,
Ray

Re: [algogeeks] Print binary tree in spiral

bansal...@gmail.com (dinesh bansal) — Fri, 20 Nov 2009 04:27:16 UT

store the nodes in an array at their specific locations. At the end, display
the nodes from the array.

Thanks,
--
Dinesh Bansal
The Law of Win says, "Let's not do it your way or my way; let's do it the
best way."

Re: Find nearest point

gene.ress...@gmail.com (Gene) — Thu, 19 Nov 2009 00:47:30 UT

This is called ... wait for it ... the "nearest neighbor search"
problem. Plug that into your favorite search engine. You'll get some
of the solutions already presented here and quite a few more.

Re: Find nearest point

rpbol...@gmail.com (Ralph Boland) — Wed, 18 Nov 2009 18:24:39 UT

The standard solution to this problem is to use a Voronoi diagram.
I am only familiar with the Euclidean version but I see no problem
constructing a Voronoi diagram on the surface of a sphere.

Ralph Boland

Re: [algogeeks] Ruby on rails help

raikra...@gmail.com (rahul rai) — Wed, 18 Nov 2009 12:08:02 UT

hello; can any body give me a link to download to THE SOLUTION MANNUAL
TO CLRS ALGORITHMS TEXTBOOK

I NEED IT URGRNTLY

Re: [algogeeks] Ruby on rails help

1986mo...@gmail.com (monty 1987) — Wed, 18 Nov 2009 11:33:21 UT

Ye naya Ruby on Rails ka kya funda hai????????

On Wed, Nov 18, 2009 at 9:37 AM, nitin mathur

Re: Find nearest point

j.bean.ea...@gmail.com (jbe) — Wed, 18 Nov 2009 11:13:12 UT

This is quite closely related to boids: [link]
Simply put, each boid is aware of its near neighbours: not just the
nearest one, but all that are nearer than some chosen distance. For
that, the space is divided into partitions that keep track of the
boids that are are within it, and also each boid knows in which

Ruby on rails help

nitinkumar.mat...@gmail.com (nitin mathur) — Wed, 18 Nov 2009 04:07:35 UT

Is there anybody working on Ruby on Rails..Plzz reply if there..

Thnx
Nitin Mathur
Joan Crawford<[link]>
- "I, Joan Crawford, I believe in the dollar. Everything I earn, I
spend."

Print binary tree in spiral

nayanish.hi...@gmail.com (Nayn) — Wed, 18 Nov 2009 02:35:57 UT

Hi guys,
Recently I came across a problem. We've to display a binary tree in
spiral.
1. We need to print the nodes in BFS manner.
2. The nodes should be displayed in alternate direction; in one level
from left to right and in next level right to left.
Needless to mention, we need least time complex solution.

Re: [algogeeks] Find nearest point

harishp...@gmail.com (Algoose Chase) — Tue, 17 Nov 2009 17:22:10 UT

Hi ,

I dont mean to present the exact solution but a trivial and
(hopefully)possible one.
Maintain 2 <latitude,longitude> vectors one sorted based on Latitude values
and other sorted based on Longitude values.
Given a coordinate say (x,y) , from the vector sorted based on latitudes
identify the coordinates whose latitude is close to X and keep a track of

Re: [algogeeks] Find nearest point

iitm.adityashan...@gmail.com (Aditya Shankar) — Tue, 17 Nov 2009 16:26:09 UT

2009/11/17 Aditya Shankar <iitm.adityashan...@gmail.com>

Re: [algogeeks] Find nearest point

iitm.adityashan...@gmail.com (Aditya Shankar) — Tue, 17 Nov 2009 16:17:55 UT

Hi,
Have a look at kd-trees.

Regards
Aditya Shankar

2009/11/17 Tiago Reul <tiagor...@gmail.com>

Re: Find nearest point

ptroc...@gmail.com (Paksas) — Tue, 17 Nov 2009 22:51:17 UT

At it simplest, you could use a spatial partitioning structure of some
sort - I'm guessing a quadtree would be more than perfect in this
case. It would cut down your search time to O(lg(n)).

The problem becomes a bit more complicated if you assume the people
can move (well - that's obvious, but maybe your problem doesn't

Find nearest point

tiagor...@gmail.com (Tiago Reul) — Tue, 17 Nov 2009 14:09:25 UT

Suppose that you have the position of each person in the world.
Position is the pair (latitude, longitude).

How to represent the data so that I can find the nearest person
from a point (ö,ë) without comparing to every pair in the collection?