[algogeeks] Re: Finding the repeated element

2012-07-23 Thread Rahul Kumar
what is the time complexity for the code ? #includeiostream using namespace std; main() { int arr[] = { 2,3,4,9,2,7}; int *ptr1 = arr[0]; int *ptr2 = arr[1]; const int SIZE = sizeof arr / sizeof arr[0]; while(1) { if(*ptr1 ==

Re: [algogeeks] Re: Finding the repeated element

2012-07-23 Thread Arun Kindra
This will help u http://www.geeksforgeeks.org/archives/570 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to

Re: [algogeeks] Re: Finding the repeated element

2012-07-23 Thread Dave
@Arun: The referenced algorithm solves the wrong problem. The problem given has n-2 unique elements and 1 element repeated twice. The referenced algorithm has n-1 elements that occur in pairs and one that is unique; xoring will solve this problem, but it won't help solve the given one. Dave

[algogeeks] Re: Finding the repeated element

2012-07-19 Thread deepikaanand
http://ideone.com/vuAse -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To view this discussion on the web visit https://groups.google.com/d/msg/algogeeks/-/rbiZjy8dcgEJ. To post to this group, send email to algogeeks@googlegroups.com. To

Re: [algogeeks] Re: Finding the repeated element

2012-07-19 Thread Saurabh Yadav
@deepikaanand (checksum 1 100) will it work ? as i know int has only 32 bits !! Thanks Regards Saurabh Yadav -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To

[algogeeks] Re: Finding the repeated element

2012-07-15 Thread santosh thota(IITG)
Could u please tell me the way to find number repeated odd number of time using X-oR..?? On Sunday, 27 November 2011 00:49:59 UTC+5:30, Gene wrote: Isn't this overkill? If you're already using a set, just check the set before you insert each new element, and you'll discover the duplicates:

[algogeeks] Re: Finding the repeated element

2011-12-06 Thread Dave
Atul: The original poster asked for an algorithm that is O(n) in time and O(1) space. So please tell us how you are going to sort the array with those limitations. Dave On Dec 6, 1:35 am, atul anand atul.87fri...@gmail.com wrote:  Given : 4 2 8 9  5 1 9 sort the array. sorting: 1 2 4 5 8 9

Re: [algogeeks] Re: Finding the repeated element

2011-12-06 Thread atul anand
@Dave : sorry , i considered sorting a prerequisite for the given problem . should have read it properly before posting. On Tue, Dec 6, 2011 at 8:56 PM, Dave dave_and_da...@juno.com wrote: Atul: The original poster asked for an algorithm that is O(n) in time and O(1) space. So please tell us

Re: [algogeeks] Re: Finding the repeated element

2011-12-05 Thread atul anand
Given : 4 2 8 9 5 1 9 sort the array. sorting: 1 2 4 5 8 9 9 for ( i = 0 ; i len ; i++) { if( i != len-1 ) { if (arr[i]==arr[i+1]) { printf(\nfound repeated element\n); break; } } } On Mon, Nov 28, 2011 at 1:24

[algogeeks] Re: Finding the repeated element

2011-11-26 Thread Gene
Isn't this overkill? If you're already using a set, just check the set before you insert each new element, and you'll discover the duplicates: S = empty while i = input item existss if i in S output i has a duplicate; insert i in S end XOR is generally useful only for detecting a single item

Re: [algogeeks] Re: Finding the repeated element

2011-11-24 Thread kumar raja
@kunzmilan : i did not get u, once explain with example... On 23 November 2011 23:47, kunzmilan kunzmi...@atlas.cz wrote: On 24 lis, 07:02, kumar raja rajkumar.cs...@gmail.com wrote: In the given array all the elements occur single time except one element which occurs 2 times find it

[algogeeks] Re: Finding the repeated element

2011-11-24 Thread ravu sairam
I have an O(n) space and time solution by using hashing . Firstly, make a hash table by using a hash function for each of the number in the array. After that, go through the hash table to see whether there are any repetitions for the same entry. -- You received this message because you are

Re: [algogeeks] Re: Finding the repeated element

2011-11-24 Thread shady
hashing is not that simple, can you tell your hash function ? On Thu, Nov 24, 2011 at 6:26 PM, ravu sairam ravu...@gmail.com wrote: I have an O(n) space and time solution by using hashing . Firstly, make a hash table by using a hash function for each of the number in the array. After that, go

Re: [algogeeks] Re: Finding the repeated element

2011-11-24 Thread kumar raja
@ravu sairam: Suppose the hashing is banned ,now what is ur solution??? Hashing is quite theoretical concept with time complexity O(1). But it will not be the case every time.so suggest some other better solution I used to thought of using count array ,but again its size is not O(n), its size

Re: [algogeeks] Re: Finding the repeated element

2011-11-24 Thread shady
find it in O(n) time and O(1) space, are you sure that it is possible to do it in O(n) time ? On Thu, Nov 24, 2011 at 6:59 PM, kumar raja rajkumar.cs...@gmail.comwrote: @ravu sairam: Suppose the hashing is banned ,now what is ur solution??? Hashing is quite theoretical concept with time

Re: [algogeeks] Re: Finding the repeated element

2011-11-24 Thread kumar raja
@shady : i am not sure , if u can do it with O(n) space as well it is fine for me . but once try whether it is possible in O(1) space. On 24 November 2011 05:42, shady sinv...@gmail.com wrote: find it in O(n) time and O(1) space, are you sure that it is possible to do it in O(n) time ? On

Re: [algogeeks] Re: Finding the repeated element

2011-11-24 Thread sunny agrawal
i also doubt about the time and space complexity of the problem, i has been asked a number of times with these constraints but never been answered the required, as far as i remember the best solution to this problem that has been discussed so far is using hashing and that too theoretically having

Re: [algogeeks] Re: Finding the repeated element

2011-11-24 Thread shady
i don't think there is an O(n) time solution for this... bcoz there are no constraints on the values, and on the number of values in the array. On Thu, Nov 24, 2011 at 7:15 PM, kumar raja rajkumar.cs...@gmail.comwrote: @shady : i am not sure , if u can do it with O(n) space as well it is fine

[algogeeks] Re: Finding the repeated element

2011-11-24 Thread Gene
Finding duplicates in a multiset is a pretty standard problem. I've only ever heard of two solutions, and it's unlikely there are others. One is to sort, which will place duplicates adjacent to each other, so you can find them by comparing a[i] with a[i+i] for all I. This algorithm is O(sorting

[algogeeks] Re: Finding the repeated element

2011-11-24 Thread kunzmilan
On 24 lis, 09:09, kumar raja rajkumar.cs...@gmail.com wrote: @kunzmilan : i did not get  u, once explain with example... On 23 November 2011 23:47, kunzmilan kunzmi...@atlas.cz wrote: Matrix M 0 1 0 0 1 0 1 0 0 multiplied with M(T) 0 0 1 1 1 0 0 0 0 gives 1 0 0 0 2 0 0 0 0. On its diagonal

Re: [algogeeks] Re: Finding the repeated element

2011-11-24 Thread kumar raja
@kunzmilan : Can u please maintain the clarity ?? How did u find the M if the list is 4 2 8 9 5 1 9 how M looks like ?? please elaborate it... On 24 November 2011 06:15, kunzmilan kunzmi...@atlas.cz wrote: On 24 lis, 09:09, kumar raja rajkumar.cs...@gmail.com wrote: @kunzmilan : i did not

Re: [algogeeks] Re: Finding the repeated element

2011-11-24 Thread Anup Ghatage
@kunzmilan Nice idea, how do you decide the row-size or column-size of the matrix? On Thu, Nov 24, 2011 at 8:00 PM, kumar raja rajkumar.cs...@gmail.comwrote: @kunzmilan : Can u please maintain the clarity ?? How did u find the M if the list is 4 2 8 9 5 1 9 how M looks like ?? please

Re: [algogeeks] Re: Finding the repeated element

2011-11-24 Thread kumar raja
@Anup: Atleast u tell me how the M has formed??? On 24 November 2011 11:21, Anup Ghatage ghat...@gmail.com wrote: @kunzmilan Nice idea, how do you decide the row-size or column-size of the matrix? On Thu, Nov 24, 2011 at 8:00 PM, kumar raja rajkumar.cs...@gmail.comwrote: @kunzmilan : Can

Re: [algogeeks] Re: Finding the repeated element

2011-11-24 Thread Ankur Garg
^^+1..how matrix formed ?? But as Gene said we can use a set to store all the unique elements Now we xor all the set elements and then xor them with the elements of the array . This wud give us the repeating element as all the elements coming once will be 0(xored twice) and repeating element wud

[algogeeks] Re: Finding the repeated element

2011-11-23 Thread kunzmilan
On 24 lis, 07:02, kumar raja rajkumar.cs...@gmail.com wrote: In the given array all the elements occur single time except  one element which occurs  2 times find it in O(n) time and O(1) space. e.g.  2 3 4 9 3 7 output :3 If such a solution exist can we extend the logic to find All the