Dave - Can you elaborate on how you can do this - "you can determine whether the low order bit of the missing number is 0 or 1"
On Jun 26, 2:32 pm, Kamakshii Aggarwal <kamakshi...@gmail.com> wrote: > thanks dave.. > > On 6/26/11, Dave <dave_and_da...@juno.com> wrote: > > > @Kamakshii: In O(n), you can determine whether the low order bit of > > the missing number is 0 or 1. You can eliminate the approximately n/2 > > numbers that do not have this low order bit. Then, in O(n/2), you can > > determine the next-to-low order bit. Etc. O(n) + O(n/2) + O(n/4) + ... > > = O(n). > > > Dave > > > On Jun 26, 2:41 am, Kamakshii Aggarwal <kamakshi...@gmail.com> wrote: > >> @dave:can u please give the divide and conquer solution > > >> On 6/26/11, Kamakshii Aggarwal <kamakshi...@gmail.com> wrote: > > >> > @aditya:it is given in the question that u cannot access the entire > >> > element in single operaion..therefore both your above solution do not > >> > hold for this question. > > >> > On 6/25/11, sunny agrawal <sunny816.i...@gmail.com> wrote: > >> >> @Dave > >> >> yes u r right that integers means it can be big integers too. > >> >> generally when we talk about integers, they are 32 bit integers in > >> >> Programing/Algorithm Questions > >> >> so i was assuming that here > > >> >> and about my solution - yes it will be O(nlgn) or O(nw) not acceptable > >> >> for > >> >> given Q :( > > >> >> and yes a Divide and Conquer solution can do it in O(n). I just came to > >> >> know > >> >> ..thanks > >> >> i little bit similer to my approach............Nice One > > >> >> On Sat, Jun 25, 2011 at 9:15 PM, Dave <dave_and_da...@juno.com> wrote: > > >> >>> @Sunny. You are reading too much into that. There is no mention that > >> >>> the data are 32-bit integers. Perhaps they are big integers. What we > >> >>> know is that the data are not characters, real numbers, rational > >> >>> numbers, floating point, etc. > > >> >>> Your algorithm is O(n*w), where w is the word size. As I said, a > >> >>> divide-and-conquer algorithm can find the missing number in O(n). > >> >>> Furthermore, this is independent of the word size. > > >> >>> Dave > > >> >>> On Jun 24, 11:44 pm, sunny agrawal <sunny816.i...@gmail.com> wrote: > >> >>> > @Dave it is given in Question that elements of array are integer > > >> >>> > On Sat, Jun 25, 2011 at 7:17 AM, Dave <dave_and_da...@juno.com> > >> >>> > wrote: > >> >>> > > @Sunny: What makes you think that the integers are 32 bits in > >> >>> > > length. > >> >>> > > Remember that O(.) notation applies as n --> infinity. Thus, O(n > >> >>> > > log > >> >>> > > n) is correct for a naive algorithm. But a little thought can give > >> >>> > > a > >> >>> > > divide-and-conquer algorithm which is O(n). > > >> >>> > > Dave > > >> >>> > > On Jun 24, 8:44 am, sunny agrawal <sunny816.i...@gmail.com> wrote: > >> >>> > > > hmm i also doubt that > >> >>> > > > but it is Strictly O(32n) not O(nlgn) where lgn <= 32 depending > >> >>> > > > upon > >> >>> > > value > >> >>> > > > of n > > >> >>> > > > On Fri, Jun 24, 2011 at 1:10 PM, rizwan hudda > >> >>> > > > <rizwanhu...@gmail.com > > >> >>> > > wrote: > >> >>> > > > > @sunny: Think again, your solution will take O(n*log(n)), > >> >>> > > > > where > >> >>> log(n) > >> >>> > > is > >> >>> > > > > the number of bits to represent > >> >>> > > > > the number. > > >> >>> > > > > On Thu, Jun 23, 2011 at 6:51 PM, Sriganesh Krishnan < > >> >>> 2448...@gmail.com > >> >>> > > >wrote: > > >> >>> > > > >> can you explain me....what the logic is...behind the xor > >> >>> > > operation?...is > >> >>> > > > >> it like inversion or encryption? > > >> >>> > > > >> On Thu, Jun 23, 2011 at 11:59 AM, sunny agrawal < > >> >>> > > sunny816.i...@gmail.com>wrote: > > >> >>> > > > >>> initially compute xor of all the values from 0 to n in a > >> >>> > > > >>> variable > >> >>> > > Temp > >> >>> > > > >>> so temp = 0^1^2........^n > >> >>> > > > >>> let result is used to store the missing number > >> >>> > > > >>> for each ith bit of missing number where i = 0-31 we can > >> >>> > > > >>> find > >> >>> > > > >>> it > >> >>> as > >> >>> > > > >>> following > >> >>> > > > >>> ith bit of result = (xor of all ith bits of values of array) > >> >>> xored > >> >>> > > with > >> >>> > > > >>> (ith > >> >>> > > > >>> bit of temp) > > >> >>> > > > >>> On Thu, Jun 23, 2011 at 12:25 AM, oppilas . < > >> >>> > > jatka.oppimi...@gmail.com>wrote: > > >> >>> > > > >>>> Is the array sorted? > >> >>> > > > >>>> In A[1..n], one number is missing from 0 to N. So, > >> >>> > > > >>>> A[5]={--INF, 2,1,3,0} is a valid case? > > >> >>> > > > >>>> On Wed, Jun 22, 2011 at 11:51 PM, RollBack < > >> >>> rajeevr...@gmail.com > >> >>> > > >wrote: > > >> >>> > > > >>>>> An array A[1...n] contains all the integers from 0 to n > >> >>> > > > >>>>> except > >> >>> for > >> >>> > > one > >> >>> > > > >>>>> number which is > >> >>> > > > >>>>> missing. In this problem, we cannot access an entire > >> >>> > > > >>>>> integer > >> >>> > > > >>>>> in > >> >>> A > >> >>> > > with > >> >>> > > > >>>>> a single opera- > >> >>> > > > >>>>> tion. The elements of A are represented in binary, and the > >> >>> > > > >>>>> only > >> >>> > > > >>>>> operation we can use > >> >>> > > > >>>>> to access them is “fetch the jth bit of A[i]”, which takes > >> >>> constant > >> >>> > > > >>>>> time. Write code to > >> >>> > > > >>>>> find the missing integer. Can you do it in O(n) time? > >> >>> > > > >>>>> _ > >> >>> > > > >>>>> _ _____________________________________________ > > >> >>> > > > >>>>> Rajeev N Bharshetty > >> >>> > > > >>>>> I Blog @www.opensourcemania.co.cc > > >> >>> > > > >>>>> -- > >> >>> > > > >>>>> 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 > >> >>> > > > >>>>> algogeeks+unsubscr...@googlegroups.com. > >> >>> > > > >>>>> For more options, visit this group at > >> >>> > > > >>>>>http://groups.google.com/group/algogeeks?hl=en. > > >> >>> > > > >>>> -- > >> >>> > > > >>>> 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 > >> >>> > > > >>>> algogeeks+unsubscr...@googlegroups.com. > >> >>> > > > >>>> For more options, visit this group at > >> >>> > > > >>>>http://groups.google.com/group/algogeeks?hl=en. > > >> >>> > > > >>> -- > >> >>> > > > >>> Sunny Aggrawal > >> >>> > > > >>> B-Tech IV year,CSI > >> >>> > > > >>> Indian Institute Of Technology,Roorkee > > >> >>> > > > >>> -- > >> >>> > > > >>> 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 > >> >>> > > > >>> algogeeks+unsubscr...@googlegroups.com. > >> >>> > > > >>> For more options, visit this group at > >> >>> > > > >>>http://groups.google.com/group/algogeeks?hl=en. > > >> >>> > > > >> -- > >> >>> > > > >> 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 > >> >>> > > > >> algogeeks+unsubscr...@googlegroups.com. > >> >>> > > > >> For more options, visit this group at > >> >>> > > > >>http://groups.google.com/group/algogeeks?hl=en. > > >> >>> > > > > -- > >> >>> > > > > Thanks and regards > >> >>> > > > > Rizwan A Hudda > >> >>> > > > >http://sites.google.com/site/rizwanhudda > > >> >>> > > > > -- > >> >>> > > > > 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 > >> >>> > > > > algogeeks+unsubscr...@googlegroups.com. > >> >>> > > > > For more options, visit this group at > >> >>> > > > >http://groups.google.com/group/algogeeks?hl=en. > > >> >>> > > > -- > >> >>> > > > Sunny Aggrawal > >> >>> > > > B-Tech IV year,CSI > >> >>> > > > Indian Institute Of Technology,Roorkee- Hide quoted text - > > >> >>> > > > - Show quoted text - > > >> >>> > > -- > >> >>> > > 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 > >> >>> > > algogeeks+unsubscr...@googlegroups.com. > >> >>> > > For more options, visit this group at > >> >>> > >http://groups.google.com/group/algogeeks?hl=en. > > >> >>> > -- > >> >>> > Sunny Aggrawal > >> >>> > B-Tech IV year,CSI > >> >>> > Indian Institute Of Technology,Roorkee- Hide quoted text - > > >> >>> > - Show quoted text - > > >> >>> -- > >> >>> 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 > >> >>> algogeeks+unsubscr...@googlegroups.com. > >> >>> For more options, visit this group at > >> >>>http://groups.google.com/group/algogeeks?hl=en. > > >> >> -- > >> >> Sunny Aggrawal > >> >> B-Tech IV year,CSI > >> >> Indian Institute Of Technology,Roorkee > > >> >> -- > >> >> 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 > >> >> algogeeks+unsubscr...@googlegroups.com. > >> >> For more options, visit this group at > >> >>http://groups.google.com/group/algogeeks?hl=en. > > >> > -- > >> > Regards, > >> > Kamakshi > >> > kamakshi...@gmail.com > > >> -- > >> Regards, > >> Kamakshi > >> kamakshi...@gmail.com- Hide quoted text - > > >> - Show quoted text - > > > -- > > You received > > ... > > read more » -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. 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