Day25.java

import java.util.*;

class Graph {
    private int vertices;
    private Map<Integer, List<Integer>> adjacencyList;

    public Graph(int vertices) {
        this.vertices = vertices;
        this.adjacencyList = new HashMap<>();
        for (int i = 0; i < vertices; i++) {
            adjacencyList.put(i, new LinkedList<>());
        }
    }

    public void addEdge(int source, int destination) {
        adjacencyList.get(source).add(destination);
        adjacencyList.get(destination).add(source); 
    }

    public void printGraph() {
        for (Map.Entry<Integer, List<Integer>> entry : adjacencyList.entrySet()) {
            System.out.print("Vertex " + entry.getKey() + " is connected to: ");
            for (int neighbor : entry.getValue()) {
                System.out.print(neighbor + " ");
            }
            System.out.println();
        }
    }
}

public class Day25 {
    public static void main(String[] args) {
        Graph graph = new Graph(5);
        graph.addEdge(0, 1);
        graph.addEdge(0, 2);
        graph.addEdge(1, 3);
        graph.addEdge(2, 4);

        System.out.println("Graph representation:");
        graph.printGraph();
    }
}