public static int[] dfs(final IGraph g, final int vertex) {
final int len = g.getNumVertices();
pred = new int[len];
color = new int[len];
for (int i = 0; i < len; i++) {
pred[i] = i;
color[i] = WHITE;
}
visit(g, vertex);
for (final int unvisited : g.getVertices()) {
if (WHITE != color[unvisited]) {
continue;
}
visit(g, unvisited);
}
return pred;
}
private static void visit(final IGraph g, final int vertex) {
color[vertex] = GREY;
for (final int neighbor : g.getNeighbors(vertex)) {
if (WHITE != color[neighbor]) {
continue;
}
pred[neighbor] = vertex;
visit(g, neighbor);
}
color[vertex] = BLACK;
}