import java.io.PrintWriter;
/**
* Incidence matrix implementation for the GraphInterface interface.
*
* Your task is to complete the implementation of this class. You may add methods, but ensure your modified class compiles and runs.
*
* @author Jeffrey Chan, 2021.
*/
public class IncidenceMatrix extends AbstractGraph
{
/**
* Contructs empty graph.
*/
public IncidenceMatrix() {
// Implement me!
} // end of IncidenceMatrix()
public void addVertex(String vertLabel) {
// Implement me!
} // end of addVertex()
public void addEdge(String srcLabel, String tarLabel) {
// Implement me!
} // end of addEdge()
public void toggleVertexState(String vertLabel) {
// Implement me!
} // end of toggleVertexState()
public void deleteEdge(String srcLabel, String tarLabel) {
// Implement me!
} // end of deleteEdge()
public void deleteVertex(String vertLabel) {
// Implement me!
} // end of deleteVertex()
public String[] kHopNeighbours(int k, String vertLabel) {
// Implement me!
// please update!
return null;
} // end of kHopNeighbours()
public void printVertices(PrintWriter os) {
// Implement me!
} // end of printVertices()
public void printEdges(PrintWriter os) {
// Implement me!
} // end of printEdges()
} // end of class IncidenceMatrix