code: public int getNumberOfSteps() {
  		int result = 0;
  
  		final Queue<TraceStep> queue = new LinkedList<>();
  		queue.add(root);
  
  		while (!queue.isEmpty()) {
  			final TraceStep currentTraceStep = queue.poll();
  
  			result++;
  
  			final List<TraceStep> children = currentTraceStep.getChildren();
  			if (!children.isEmpty()) {
  				queue.addAll(children);
  			}
  		}
  
  		return result;
  	}
docs: Calculates the number of steps.
  
  @return the number of steps