Yup Terence is right. On Fri, Feb 5, 2010 at 11:42 AM, Terence <technic....@gmail.com> wrote:
> No. This works for all cases. Xor is commutative. > > > On 2010-2-5 13:37, srinivas chintagunta wrote: > > I think this works if elements are sorted . Is it correct? > > On Mon, Feb 1, 2010 at 5:07 PM, sachin <sachin_mi...@yahoo.co.in> wrote: > >> A way to solve this problem would be using xor(exclusive OR) >> xor all the elements from 1 to n.Call it A >> xor all the elements of the array into a variable B >> Now missing element = A xor B >> It works this way >> xor-ing an element with itself gives 0(p xor p=0) >> xor-ing an element with 0 gives the element itself(p xor 0=p) >> xor-ing an element with 1 gives the complement of element(p xor >> 1=complement(p)) >> >> Now suppose you are given 4 elements and you have to find the missing >> 5th element >> A=1 xor 2 xor 3 xor 4 xor 5; >> B=ar[1] xor ar[2] xor ar[3] xor ar[4]; >> >> let array be {2,5,3,1} >> thus, B=1 xor 2 xor 3 xor 5; >> >> Now A xor B = (1 xor 1) xor (2 xor 2) xor (3 xor 3) xor (5 xor 5) xor >> 4 = 0 xor 0 xor 0 xor 0 xor 4 = 4(the missing element). >> >> Regards >> Sachin >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Algorithm Geeks" group. >> To post to this group, send email to algoge...@googlegroups.com. >> To unsubscribe from this group, send email to >> algogeeks+unsubscr...@googlegroups.com<algogeeks%2bunsubscr...@googlegroups.com> >> . >> For more options, visit this group at >> http://groups.google.com/group/algogeeks?hl=en. >> >> > > > -- > Srinivas Chintagunta, > Hyderabad. > -- > You received this message because you are subscribed to the Google Groups > "Algorithm Geeks" group. > To post to this group, send email to algoge...@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 algoge...@googlegroups.com. > To unsubscribe from this group, send email to > algogeeks+unsubscr...@googlegroups.com<algogeeks%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/algogeeks?hl=en. > -- -- Atul Verma -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to algoge...@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.