Back edges are the key to finding a cycle in an undirected graph. Condition for Back edge is vertex(u,v):v that we are trying to explore from (u) should not be the parent of u. http://codepad.org/t7Y5wshb
On Tue, Jun 15, 2010 at 5:25 AM, Rohit Saraf <rohit.kumar.sa...@gmail.com>wrote: > @vivek : was that a joke? > > -------------------------------------------------- > Rohit Saraf > Second Year Undergraduate, > Dept. of Computer Science and Engineering > IIT Bombay > http://www.cse.iitb.ac.in/~rohitfeb14<http://www.cse.iitb.ac.in/%7Erohitfeb14> > > > On Mon, Jun 14, 2010 at 11:40 AM, souravsain <souravs...@gmail.com> wrote: > >> @sharad: Do you have some article that explains cycle detection in >> bfs? Will be of help if you can share that or book or so which >> explains cycle detection via bfs. >> >> @amit: Both in directed and undirected graphs you can find a cycle in >> O(|v|) time using a dfs. See "Algorithm Design Manual" Second Edition, >> chapter 5 by Stiev. S. Skiena. Its a very good explanation. >> >> On Jun 14, 6:19 am, Rohit Saraf <rohit.kumar.sa...@gmail.com> wrote: >> > In any directed graph just check if dfs has a back edge. For >> > undirected, check if there is a nontree edge >> > >> > -- >> > -------------------------------------------------- >> > Rohit Saraf >> > Second Year Undergraduate, >> > Dept. of Computer Science and Engineering >> > IIT >> > Bombayhttp://www.cse.iitb.ac.in/~rohitfeb14<http://www.cse.iitb.ac.in/%7Erohitfeb14> >> >> -- >> 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. > -- 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.
