ya it works on independent set but will try it for maximal indpendent set. i
guess it will fail if it fails back to drawing room );

On Mon, May 2, 2011 at 9:24 PM, Rahul Gulati <[email protected]>wrote:

> Okay! Try this - Write a brute force program that can find the maximal
> independent for say a graph of size 20. Create a test file (some 50 - 100
> random testcases). Test the outputs of the brute force program with that of
> your algorithm. You'll find the bugs/corner-cases.
>
> Regards,
>
> Rahul
>
>
> On Mon, May 2, 2011 at 9:20 PM, prajay shetty <[email protected]>wrote:
>
>> ya it does because see here
>>
>> http://en.wikipedia.org/wiki/Complete_graph
>>
>> considering this
>>
>> if u apply a dfs on this on k=10
>> dfs will travel all long   1,2,3,4,5
>>
>> now  when we apply bfs we will get it as
>>      1
>> 2 3 4 5
>>
>> so all 2,3,4,5 will get eliminated since all are connected to the nodes
>> marked as yellow and  if u select a node  it will give u 1 then all gets
>> eliminated  ie 2 ,3,4,5
>>
>> thanks rahul for your question
>>
>>
>> On Mon, May 2, 2011 at 9:12 PM, Rahul Gulati <[email protected]>wrote:
>>
>>> Try out some corner cases like complete graphs, etc. Does your algorithm
>>> return 1 for a complete graph?
>>>
>>> On Mon, May 2, 2011 at 9:09 PM, prajay shetty 
>>> <[email protected]>wrote:
>>>
>>>> thanks for the admin coorporation please post the problem
>>>>
>>>>
>>>> On Mon, May 2, 2011 at 8:19 PM, prajay shetty <[email protected]
>>>> > wrote:
>>>>
>>>>>
>>>>> Hey all,
>>>>>
>>>>> Last week  i was going trough corfment this is not a gcj problem but i
>>>>> had wrote an algorithm on np complete that is an independent set problem
>>>>> which has no cycle and no weight i had tried this algorithm on this type 
>>>>> of
>>>>> graphs , can anyone provied me with counter example if any ,I taught this
>>>>> was the good one comunicate with you members since most of you will be 
>>>>> good
>>>>> at DSA atleast more than me ): thanks for any help in the problem
>>>>>
>>>>> so here is our graph which has following properties as an example
>>>>> 1) node 1 is connected to node 2
>>>>> 2) node 2 is connected to node 3
>>>>> 3) node 3 is connected to node 1
>>>>> 4)node 2 is  connected to node 5
>>>>> 5) node 2 is connected to node 4
>>>>> 6) node 5 is connectd to node 6
>>>>> 7)node 4 is connected to node 5
>>>>> 8) node 3 is connected to node 7
>>>>> 9) node 7 is connected to node 8
>>>>> 10) node 8 is connected to node 3
>>>>>
>>>>>
>>>>> First by seeing the graph we have independent set  is 1,4,6,8
>>>>> Algorithm
>>>>>
>>>>> 1)We genearte dfs on graph g
>>>>> 2) We genearte bfs on g
>>>>> 3)DFS: here we modify our dfs a bit insteda as we go through dfs  we
>>>>> color first node as blue and we dont color the next node  and we color the
>>>>> next node  blue this continues till we  reach a dead end.,we list all the
>>>>> node that we marked as blue.
>>>>> for example we get the output as 1,3,5  now we explore 3  and we dont
>>>>> color 7 and then we color 8  like this we procceed, output is 1,3,4,6,8
>>>>> 4) BFS: we generate bfs, then  once we got the list of nodes we
>>>>> maintain a pair node in an array as parent child in our array for example 
>>>>> we
>>>>> store 1->2,3 and 2->4,5 and 3->7,8 for bfs we can just reduce the memory
>>>>> space by working on efficient ds on this.
>>>>> 5) then we color all the node as yellow in our bfs tree for the nodes
>>>>> that we obtain in step 3
>>>>> 6)now we check if the node that is in the list has a node  connected to
>>>>> it  colored as yellow ,if yes we delete it from our final list and in this
>>>>> way we get we remove 3 as 3  is connected to 1
>>>>> so we get our final list as 1,4,6,8
>>>>>
>>>>> just want to check if there is any counter example for this ...thanks
>>>>> for your help
>>>>>
>>>>>
>>>>> Note: step 3 can be done with step 1 and step 2 can be done with step 4
>>>>>
>>>>>
>>>>> --
>>>>> Regards ,Prajay
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> Regards ,Prajay
>>>>
>>>> --
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>>>
>>>
>>>
>>> --
>>> Rahul Gulati
>>> [email protected]
>>> Department of Computer Science
>>> Jaypee Institute of Information Technology (Deemed University)
>>> India
>>>
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>>
>>
>>
>> --
>> Regards ,Prajay
>>
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>
>
>
> --
> Rahul Gulati
> [email protected]
> Department of Computer Science
> Jaypee Institute of Information Technology (Deemed University)
> India
>
>  --
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>



-- 
Regards ,Prajay

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