ankur is right this problem is similar to the problem of converting a matrix to zero matrix
On Tue, Jan 4, 2011 at 8:36 PM, Ankur Khurana <ankur.kkhur...@gmail.com>wrote: > how are they similar ? > > > On Tue, Jan 4, 2011 at 8:31 PM, jennmeedo <jennme...@gmail.com> wrote: > >> Generalization algorithm for the 8 - queens classical chess problem >> >> On Jan 4, 5:43 am, bittu <shashank7andr...@gmail.com> wrote: >> > There is a lock which is an N by N grid of switches. Each switch can >> > be in one of two states (on/off). The lock is unlocked if all the >> > switches are on. The lock is built in such a way that, if you toggle >> > some switch, all the switches in its row and its column toggle too >> > >> > Give an algorithm which, given N and a configuration of the N^2 >> > switches, will tell you whether the lock can be unlocked by a sequence >> > of switch toggles >> > >> > Note 1: Can be done in O(N^2) time and O(1) space. >> > Note 2: You just need to tell if a sequence which unlocks the lock >> > exists (and not the actual sequence) >> >> -- >> 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. >> >> > -- > 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. > -- Regards Aditya Kumar B-tech 3rd year Computer Science & Engg. MNNIT, Allahabad. -- 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.