static int countChildren(final Tree<?, ?> tree) {
		int cnt = tree.childCount();
		for (int i = 0; i < tree.childCount(); ++i) {
			cnt += countChildren(tree.childAt(i));
		}
		return cnt;
	}
Checks if the two given trees has the same structure with the same values.

@param a the first tree
@param b the second tree
@return {@code true} if the two given trees are structurally equals,
        {@code false} otherwise
jenetics.ext/src/main/java/io/jenetics/ext/util/Trees.java