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Below is the instructions for my project
(Displaying sets of connected circles) Modify ConnectedCircles.java to display sets of connected circles in different random colors, i.e., if two circles are connected, they are displayed using the same color; otherwise, they are not in same color.
I know there is stuff that needs to be removed but this project is a 5 part one and whats not used now will me in the next....
Code:
import java.util.List;
import java.util.ArrayList;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class ConnectedCircles extends JApplet {
// Circles are stored in a list
private List<Circle> circles = new ArrayList<Circle>();
public ConnectedCircles() {
add (new CirclePanel()); // Add to circle panel to applet
}
/** Panel for displaying circles */
class CirclePanel extends JPanel {
public CirclePanel() {
addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
if (!isInsideACircle(e.getPoint())) { // Add a new circle
circles.add(new Circle(e.getX(), e.getY()));
repaint();
}
}
});
}
/** Returns true if the point is inside an existing circle */
private boolean isInsideACircle(Point p) {
for (Circle circle: circles)
if (circle.contains(p)) return true;
return false;
}
protected void paintComponent(Graphics g) {
if (circles.size() == 0) return; // Nothing to paint
super.paintComponent(g);
// Build the edges
List<AbstractGraph.Edge> edges
= new ArrayList<AbstractGraph.Edge>();
for (int i = 0; i < circles.size(); i++)
for (int j = i + 1; j < circles.size(); j++)
if (circles.get(i).overlaps(circles.get(j))) {
edges.add(new AbstractGraph.Edge(i, j));
edges.add(new AbstractGraph.Edge(j, i));
}
// Create a graph with circles as vertices
Graph<Circle> graph
= new UnweightedGraph<Circle>(edges, circles);
AbstractGraph<Circle>.Tree tree = graph.dfs(0); // a DFS tree
boolean isAllCirclesConnected =
circles.size() == tree.getNumberOfVerticesFound();
for (Circle circle: circles) {
int radius = circle.radius;
if (isAllCirclesConnected) { // All circles are connected
Random rand;
rand = new Random();
g.setColor(new Color(rand.nextInt(256),rand.nextInt(256),rand.nextInt(256)));
g.fillOval(circle.x - radius, circle.y - radius,
2 * radius, 2 * radius);
}
else // circles are not all connected
g.drawOval(circle.x - radius, circle.y - radius,
2 * radius, 2 * radius);
}
}
}
private static class Circle {
int radius = 20;
int x, y;
Circle(int x, int y) {
this.x = x;
this.y = y;
}
public boolean contains(Point p) {
double d = distance(x, y, p.x, p.y);
return d <= radius;
}
public boolean overlaps(Circle circle) {
return distance(this.x, this.y, circle.x, circle.y)
<= radius + circle.radius;
}
private static double distance(int x1, int y1, int x2, int y2) {
return Math.sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
}
}
public static void main(String[] args) {
JFrame frame = new JFrame();
JApplet applet = new ConnectedCircles();
frame.add(applet);
frame.setTitle("ConnectedCircles");
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400, 300);
frame.setVisible(true);
}
}
interface Graph<V> {
/** Return the number of vertices in the graph */
public int getSize();
/** Return the vertices in the graph */
public java.util.List<V> getVertices();
/** Return the object for the specified vertex index */
public V getVertex(int index);
/** Return the index for the specified vertex object */
public int getIndex(V v);
/** Return the neighbors of vertex with the specified index */
public java.util.List<Integer> getNeighbors(int index);
/** Return the degree for a specified vertex */
public int getDegree(int v);
/** Print the edges */
public void printEdges();
/** Clear graph */
public void clear();
/** Add a vertex to the graph */
public void addVertex(V vertex);
/** Add an edge to the graph */
public void addEdge(int u, int v);
/** Obtain a depth-first search tree */
public AbstractGraph<V>.Tree dfs(int v);
/** Obtain a breadth-first search tree */
public AbstractGraph<V>.Tree bfs(int v);
}
abstract class AbstractGraph<V> implements Graph<V> {
protected List<V> vertices = new ArrayList<V>(); // Store vertices
protected List<List<Integer>> neighbors
= new ArrayList<List<Integer>>(); // Adjacency lists
/** Construct an empty graph */
protected AbstractGraph() {
}
/** Construct a graph from edges and vertices stored in arrays */
protected AbstractGraph(int[][] edges, V[] vertices) {
for (int i = 0; i < vertices.length; i++)
this.vertices.add(vertices[i]);
createAdjacencyLists(edges, vertices.length);
}
/** Construct a graph from edges and vertices stored in List */
protected AbstractGraph(List<Edge> edges, List<V> vertices) {
for (int i = 0; i < vertices.size(); i++)
this.vertices.add(vertices.get(i));
createAdjacencyLists(edges, vertices.size());
}
/** Construct a graph for integer vertices 0, 1, 2 and edge list */
protected AbstractGraph(List<Edge> edges, int numberOfVertices) {
for (int i = 0; i < numberOfVertices; i++) {
vertices.add((V)(new Integer(i))); // vertices is {0, 1, ...}
}
createAdjacencyLists(edges, numberOfVertices);
}
/** Construct a graph from integer vertices 0, 1, and edge array */
protected AbstractGraph(int[][] edges, int numberOfVertices) {
for (int i = 0; i < numberOfVertices; i++) {
vertices.add((V)(new Integer(i))); // vertices is {0, 1, ...}
}
createAdjacencyLists(edges, numberOfVertices);
}
/** Create adjacency lists for each vertex */
private void createAdjacencyLists(
int[][] edges, int numberOfVertices) {
// Create a linked list
for (int i = 0; i < numberOfVertices; i++) {
neighbors.add(new ArrayList<Integer>());
}
for (int i = 0; i < edges.length; i++) {
int u = edges[i][0];
int v = edges[i][1];
neighbors.get(u).add(v);
}
}
/** Create adjacency lists for each vertex */
private void createAdjacencyLists(
List<Edge> edges, int numberOfVertices) {
// Create a linked list for each vertex
for (int i = 0; i < numberOfVertices; i++) {
neighbors.add(new ArrayList<Integer>());
}
for (Edge edge: edges) {
neighbors.get(edge.u).add(edge.v);
}
}
/** Return the number of vertices in the graph */
public int getSize() {
return vertices.size();
}
/** Return the vertices in the graph */
public List<V> getVertices() {
return vertices;
}
/** Return the object for the specified vertex */
public V getVertex(int index) {
return vertices.get(index);
}
/** Return the index for the specified vertex object */
public int getIndex(V v) {
return vertices.indexOf(v);
}
/** Return the neighbors of vertex with the specified index */
public List<Integer> getNeighbors(int index) {
return neighbors.get(index);
}
/** Return the degree for a specified vertex */
public int getDegree(int v) {
return neighbors.get(v).size();
}
/** Print the edges */
public void printEdges() {
for (int u = 0; u < neighbors.size(); u++) {
System.out.print(getVertex(u) + " (" + u + "): ");
for (int j = 0; j < neighbors.get(u).size(); j++) {
System.out.print("(" + u + ", " +
neighbors.get(u).get(j) + ") ");
}
System.out.println();
}
}
/** Clear graph */
public void clear() {
vertices.clear();
neighbors.clear();
}
/** Add a vertex to the graph */
public void addVertex(V vertex) {
vertices.add(vertex);
neighbors.add(new ArrayList<Integer>());
}
/** Add an edge to the graph */
public void addEdge(int u, int v) {
neighbors.get(u).add(v);
neighbors.get(v).add(u);
}
/** Edge inner class inside the AbstractGraph class */
public static class Edge {
public int u; // Starting vertex of the edge
public int v; // Ending vertex of the edge
/** Construct an edge for (u, v) */
public Edge(int u, int v) {
this.u = u;
this.v = v;
}
}
/** Obtain a DFS tree starting from vertex v */
/** To be discussed in Section 27.6 */
public Tree dfs(int v) {
List<Integer> searchOrders = new ArrayList<Integer>();
int[] parent = new int[vertices.size()];
for (int i = 0; i < parent.length; i++)
parent[i] = -1; // Initialize parent[i] to -1
// Mark visited vertices
boolean[] isVisited = new boolean[vertices.size()];
// Recursively search
dfs(v, parent, searchOrders, isVisited);
// Return a search tree
return new Tree(v, parent, searchOrders);
}
/** Recursive method for DFS search */
private void dfs(int v, int[] parent, List<Integer> searchOrders,
boolean[] isVisited) {
// Store the visited vertex
searchOrders.add(v);
isVisited[v] = true; // Vertex v visited
for (int i : neighbors.get(v)) {
if (!isVisited[i]) {
parent[i] = v; // The parent of vertex i is v
dfs(i, parent, searchOrders, isVisited); // Recursive search
}
}
}
/** Starting bfs search from vertex v */
/** To be discussed in Section 27.7 */
public Tree bfs(int v) {
List<Integer> searchOrders = new ArrayList<Integer>();
int[] parent = new int[vertices.size()];
for (int i = 0; i < parent.length; i++)
parent[i] = -1; // Initialize parent[i] to -1
java.util.LinkedList<Integer> queue =
new java.util.LinkedList<Integer>(); // list used as a queue
boolean[] isVisited = new boolean[vertices.size()];
queue.offer(v); // Enqueue v
isVisited[v] = true; // Mark it visited
while (!queue.isEmpty()) {
int u = queue.poll(); // Dequeue to u
searchOrders.add(u); // u searched
for (int w : neighbors.get(u)) {
if (!isVisited[w]) {
queue.offer(w); // Enqueue w
parent[w] = u; // The parent of w is u
isVisited[w] = true; // Mark it visited
}
}
}
return new Tree(v, parent, searchOrders);
}
/** Tree inner class inside the AbstractGraph class */
/** To be discussed in Section 27.5 */
public class Tree {
private int root; // The root of the tree
private int[] parent; // Store the parent of each vertex
private List<Integer> searchOrders; // Store the search order
/** Construct a tree with root, parent, and searchOrder */
public Tree(int root, int[] parent, List<Integer> searchOrders) {
this.root = root;
this.parent = parent;
this.searchOrders = searchOrders;
}
/** Return the root of the tree */
public int getRoot() {
return root;
}
/** Return the parent of vertex v */
public int getParent(int v) {
return parent[v];
}
/** Return an array representing search order */
public List<Integer> getSearchOrders() {
return searchOrders;
}
/** Return number of vertices found */
public int getNumberOfVerticesFound() {
return searchOrders.size();
}
/** Return the path of vertices from a vertex index to the root */
public List<V> getPath(int index) {
ArrayList<V> path = new ArrayList<V>();
do {
path.add(vertices.get(index));
index = parent[index];
}
while (index != -1);
return path;
}
/** Print a path from the root to vertex v */
public void printPath(int index) {
List<V> path = getPath(index);
System.out.print("A path from " + vertices.get(root) + " to " +
vertices.get(index) + ": ");
for (int i = path.size() - 1; i >= 0; i--)
System.out.print(path.get(i) + " ");
}
/** Print the whole tree */
public void printTree() {
System.out.println("Root is: " + vertices.get(root));
System.out.print("Edges: ");
for (int i = 0; i < parent.length; i++) {
if (parent[i] != -1) {
// Display an edge
System.out.print("(" + vertices.get(parent[i]) + ", " +
vertices.get(i) + ") ");
}
}
System.out.println();
}
}
/** Return a Hamiltonian path from the specified vertex object
* Return null if the graph does not contain a Hamiltonian path */
public List<Integer> getHamiltonianPath(V vertex) {
return getHamiltonianPath(getIndex(vertex));
}
/** Return a Hamiltonian path from the specified vertex label
* Return null if the graph does not contain a Hamiltonian path */
public List<Integer> getHamiltonianPath(int v) {
// A path starts from v. (i, next[i]) represents an edge in
// the path. isVisited[i] tracks whether i is currently in the
// path.
int[] next = new int[getSize()];
for (int i = 0; i < next.length; i++)
next[i] = -1; // Indicate no subpath from i is found yet
boolean[] isVisited = new boolean[getSize()];
// The vertices in the Hamiltonian path are stored in result
List<Integer> result = null;
// To speed up search, reorder the adjacency list for each
// vertex so that the vertices in the list are in increasing
// order of their degrees
for (int i = 0; i < getSize(); i++)
reorderNeigborsBasedOnDegree(neighbors.get(i));
if (getHamiltonianPath(v, next, isVisited)) {
result = new ArrayList<Integer>(); // Create a list for path
int vertex = v; // Starting from v
while (vertex != -1) {
result.add(vertex); // Add vertex to the result list
vertex = next[vertex]; // Get the next vertex in the path
}
}
return result; // return null if no Hamiltonian path is found
}
/** Reorder the adjacency list in increasing order of degrees */
private void reorderNeigborsBasedOnDegree(List<Integer> list) {
for (int i = list.size() - 1; i >= 1; i--) {
// Find the maximum in the list[0..i]
int currentMaxDegree = getDegree(list.get(0));
int currentMaxIndex = 0;
for (int j = 1; j <= i; j++) {
if (currentMaxDegree < getDegree(list.get(j))) {
currentMaxDegree = getDegree(list.get(j));
currentMaxIndex = j;
}
}
// Swap list[i] with list[currentMaxIndex] if necessary;
if (currentMaxIndex != i) {
int temp = list.get(currentMaxIndex);
list.set(currentMaxIndex, list.get(i));
list.set(i, temp);
}
}
}
/** Return true if all elements in array isVisited are true */
private boolean allVisited(boolean[] isVisited) {
boolean result = true;
for (int i = 0; i < getSize(); i++)
result = result && isVisited[i];
return result;
}
/** Search for a Hamiltonian path from v */
private boolean getHamiltonianPath(int v, int[] next,
boolean[] isVisited) {
isVisited[v] = true; // Mark vertex v visited
if (allVisited(isVisited))
return true; // The path now includes all vertices, thus found
for (int i = 0; i < neighbors.get(v).size(); i++) {
int u = neighbors.get(v).get(i);
if (!isVisited[u] &&
getHamiltonianPath(u, next, isVisited)) {
next[v] = u; // Edge (v, u) is in the path
return true;
}
}
isVisited[v] = false; // Backtrack, v is marked unvisited now
return false; // No Hamiltonian path exists from vertex v
}
}
class UnweightedGraph<V> extends AbstractGraph<V> {
/** Construct an empty graph */
public UnweightedGraph() {
}
/** Construct a graph from edges and vertices stored in arrays */
public UnweightedGraph(int[][] edges, V[] vertices) {
super(edges, vertices);
}
/** Construct a graph from edges and vertices stored in List */
public UnweightedGraph(List<Edge> edges, List<V> vertices) {
super(edges, vertices);
}
/** Construct a graph for integer vertices 0, 1, 2 and edge list */
public UnweightedGraph(List<Edge> edges, int numberOfVertices) {
super(edges, numberOfVertices);
}
/** Construct a graph from integer vertices 0, 1, and edge array */
public UnweightedGraph(int[][] edges, int numberOfVertices) {
super(edges, numberOfVertices);
}
}
class MyGraph<V> extends UnweightedGraph<V> {
/** Construct an empty graph */
public MyGraph() {
}
/** Construct a graph from edges and vertices stored in arrays */
public MyGraph(int[][] edges, V[] vertices) {
super(edges, vertices);
}
/** Construct a graph from edges and vertices stored in List */
public MyGraph(List<Edge> edges, List<V> vertices) {
super(edges, vertices);
}
/** Construct a graph for integer vertices 0, 1, 2 and edge list */
public MyGraph(List<Edge> edges, int numberOfVertices) {
super(edges, numberOfVertices);
}
/** Construct a graph from integer vertices 0, 1, and edge array */
public MyGraph(int[][] edges, int numberOfVertices) {
super(edges, numberOfVertices);
}
public List<List<Integer>> getConnectedComponents() {
List<List<Integer>> list = new ArrayList<List<Integer>>();
List<Integer> vertexIndices = new ArrayList<Integer>();
for (int i = 0; i < vertices.size(); i++)
vertexIndices.add(i);
while (vertexIndices.size() > 0) {
Tree tree = dfs(vertexIndices.get(0));
list.add(tree.getSearchOrders());
vertexIndices.removeAll(tree.getSearchOrders());
}
return list;
}
}
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