private static <V, E extends GEdge<V>> int getMaxChildLevel(GDirectedGraph<V, E> g,
			Map<V, Integer> levelMap, V v) {
		int maxLevel = -1;
		Collection<V> successors = g.getSuccessors(v);
		for (V child : successors) {
			Integer level = levelMap.get(child);
			if (level != null && level.intValue() > maxLevel) {
				maxLevel = level;
			}
		}
		return maxLevel;
	}
Returns true if the given strong component has no incoming edges that are outside of 
the component.  This is useful to know, as it signals that the given strong component
is reachable from outside of that component.

@param g the graph
@param strongComponent the set of vertices representing a strong component
@return true if the given strong component has no incoming edges that are outside of 
		   the component
Ghidra/Framework/Graph/src/main/java/ghidra/graph/GraphAlgorithms.java