Java Program to Implement the graph data structure

// Importing all the required packages
import java.util.*;

// implementation graph class
class Graph{
    private int V;
    private LinkedList[] adjList;

    // Constructor
    Graph(int v) {
        V = v;
        adjList = new LinkedList[V];
        for (int i = 0; i < V; i++) {
            adjList[i] = new LinkedList<>();
        }
    }

    void addEdge(int src, int dest) {
        adjList[src].add(dest);
        adjList[dest].add(src);
    }

    void printGraph() {
        for (int i = 0; i < V; i++) {
            System.out.print("Vertex " + i + " is connected to: ");
            for (int j = 0; j < adjList[i].size(); j++) {
                System.out.print(adjList[i].get(j) + " ");
            }
            System.out.println();
        }
    }
}

class Main {
    public static void main(String[] args){
        // Object for graph class
        Graph g = new Graph(5);
        
        // Adding elements in the graph
        g.addEdge(0, 1);
        g.addEdge(0, 4);
        g.addEdge(1, 2);
        g.addEdge(1, 3);
        g.addEdge(1, 4);
        g.addEdge(2, 3);
        g.addEdge(3, 4);

        g.printGraph();
    }
}