public int countTriangles(Graph<Integer> graph){
        Map<Vertex<Integer>,Boolean> visited = new HashMap<Vertex<Integer>,Boolean>();
        int count =0;
        for(Vertex<Integer> vertex : graph.getAllVertex()){
            count += DFS(vertex,visited,null);
        }
        return count;
    }
http://www.careercup.com/question?id=5988741646647296
Given an undirected graph find number of triangles in this graph
Find cycle of length 3. Pass parent in DFS search.
If there is a cycle check if my parent is neighbor of the the node 
which caused it to be a cycle.
src/com/interview/graph/NumberofTriangles.java