public static Digraph randomizeTree(
Digraph digraph, int maxChildren, int maxLevels, Random randomizer) {
int vertexIndex = 1;
Object root = new Integer(vertexIndex);
List level = Collections.singletonList(root);
digraph.addVertex(root);
for (int i = 1; i < maxLevels; i++) {
List childLevel = new ArrayList(level.size() * maxChildren);
for (Iterator j = level.iterator(); j.hasNext(); ) {
Object parent = j.next();
int childCount = randomizer.nextInt(maxChildren + 1);
for (int k = 0; k < childCount; k++) {
Object child = new Integer(++vertexIndex);
digraph.addVertex(child);
digraph.putArc(parent, child, Boolean.TRUE);
childLevel.add(child);
}
}
if (childLevel.isEmpty()) break;
level = childLevel;
}
return digraph;
}
