Hi, I am writing my bachelor thesis and I came across a study which mentions finding a 2-3 subgraph and a 2-4 subgraph of an undirected graph as one of its subtask but it doesn't mention an algorithm to do it but it just says that it is done using DFS.

I couldn't really find anything useful online solving these problems.

A 2-3 subgraph is a subgraph where each node has degree 2 or 3 in this subgraph (we remove edges which go to nodes outside the subgraph) and our task is to find a maximal 2-3 subgraph (it doesn't have to be maxmimum in terms of size just that we can't add another node to it). A 2-4 subgraph is just the same but with 2, 3 and 4.

Can anyone help by describing an algorithm or linking an article/paper?

I am wondering if problem setters test their time limits with java. Doesn't seem like it. Most C++ solution today in problem E barely passed the time limit which means it's virtually impossible to accepted in java. Not the first time this has happened in a cf round. Very frustrating.

Just received the following message : Attention!

Your solution 68541868 for the problem 1285D significantly coincides with solutions Hemose/68520332, YahiaSherif/68541868. Such a coincidence is a clear rules violation. Note that unintentional leakage is also a violation. For example, do not use ideone.com with the default settings (public access to your code). If you have conclusive evidence that a coincidence has occurred due to the use of a common source published before the competition, write a comment to post about the round with all the details. More information can be found at http://codeforces.net/blog/entry/8790. Such violation of the rules may be the reason for blocking your account or other penalties. In case of repeated violations, your account may be blocked.

I the two solutions are not even close to being similar except for the Scanner which is used by most students in our University because it was implemented by a senior in our community here is the link to the Scanner class . https://github.com/AhmadElsagheer/Competitive-programming-library/blob/master/other_algorithms/Scanner.java

PLEASE HELP !!!!! All my problems are "skipped".