DFS traversal algorithm

[alpha_1]

i have No idea how to do this

By modifying the DFS traversal algorithm, write pseudocode for an algorithm that determines whether a graph contains a cycle.

[jonnin]

the traversal is wired to touch every node once, or at least thats the usual defination of a traversal (?).

There are several ways to do this, and better ways, but this is the simple one.

Run the traversal, and at every node, create a list of what nodes are 1 step away from the current node. You now have a "map" of the entire graph; from any node, you can now "see" what nodes can be visited next. From that information, you should be able to build a test for a cycle.