import java.util.LinkedList;

public class Graph {

// Keep track of the graph size

private int numVertices;

private int numEdges;

private LinkedList<node>[] adjacencylist;

public Graph(int numVertices, int numEdges) {

this.numVertices = numVertices;

this.numEdges = numEdges;

//initialize adjacency lists for all the vertices

this.adjacencylist = new LinkedList[numVertices];

for (int i = 0; i < numVertices; i++) {

adjacencylist[i] = new LinkedList<>();

}

}

public void printGraph() {

for (int i = 0; i < this.numVertices; i++) {

LinkedList<node> list = this.adjacencylist[i];

for (int j = 0; j < list.size(); j++) {

System.out.println("vertex-" + i + " is connected to " +

list.get(j).destination + " with weight " + list.get(j).weight);

}

}

}

public int getNumVertices(){

return this.numVertices;

}

public int numEdges(){

return this.numEdges;

}

public int getWeight(int source,int destination){

if (source==destination)

return 0;

LinkedList<node> list = this.adjacencylist[source];

for (int j = 0; j < list.size(); j++) {

if(list.get(j).destination == destination)

return list.get(j).weight;

}

return Integer.MAX_VALUE;

}

public void setEgde(int source, int destination, int weight) {

node edge = new node(source, destination, weight);

this.adjacencylist[source].addLast(edge);

}

public void deleteEgde(int source, int destination) {

for (int i = 0; i < this.adjacencylist[source].size(); i++) {

if (this.adjacencylist[source].get(i).destination == destination){

this.adjacencylist[source].remove(i);

break;

}

}

}

public LinkedList<node> getList(int index){

return this.adjacencylist[index];

}

public int getAdjList(){

return this.adjacencylist.length;

}

}