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ChrisMayfieldChrisMayfield
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ch15 revisions
1 parent ce25adb commit be6bb54

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Lines changed: 157 additions & 99 deletions

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‎ch15/Cell.java‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -66,4 +66,5 @@ public void turnOff() {
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public void turnOn() {
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state = 1;
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}
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}

‎ch15/Conway.java‎

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import javax.swing.JFrame;
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/**
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* Conway's Game of Life.
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*/
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public class Conway {
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private GridCanvas grid;
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/**
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* Creates a grid with two Blinkers.
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*/
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public Conway() {
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grid = new GridCanvas(5, 10, 20);
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grid.turnOn(2, 1);
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grid.turnOn(2, 2);
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grid.turnOn(2, 3);
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grid.turnOn(1, 7);
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grid.turnOn(2, 7);
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grid.turnOn(3, 7);
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}
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/**
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* Counts the number of live neighbors around a cell.
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*
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* @param r row index
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* @param c column index
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* @return number of live neighbors
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*/
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private int countAlive(int r, int c) {
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int count = 0;
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count += grid.test(r - 1, c - 1);
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count += grid.test(r - 1, c);
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count += grid.test(r - 1, c + 1);
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count += grid.test(r, c - 1);
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count += grid.test(r, c + 1);
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count += grid.test(r + 1, c - 1);
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count += grid.test(r + 1, c);
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count += grid.test(r + 1, c + 1);
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return count;
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}
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/**
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* Apply the update rules of Conway's Game of Life.
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*
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* @param cell the cell to update
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* @param count number of live neighbors
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*/
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private static void updateCell(Cell cell, int count) {
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if (cell.isOn()) {
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if (count < 2 || count > 3) {
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// Any live cell with fewer than two live neighbors dies,
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// as if by underpopulation.
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// Any live cell with more than three live neighbors dies,
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// as if by overpopulation.
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cell.turnOff();
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}
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} else {
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if (count == 3) {
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// Any dead cell with exactly three live neighbors
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// becomes a live cell, as if by reproduction.
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cell.turnOn();
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}
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}
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}
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/**
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* Counts the neighbors before changing anything.
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*
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* @return number of neighbors for each cell
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*/
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private int[][] countNeighbors() {
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int rows = grid.numRows();
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int cols = grid.numCols();
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int[][] counts = new int[rows][cols];
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for (int r = 0; r < rows; r++) {
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for (int c = 0; c < cols; c++) {
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counts[r][c] = countAlive(r, c);
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}
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}
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return counts;
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}
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/**
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* Updates each cell based on neighbor counts.
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*
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* @param counts number of neighbors for each cell
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*/
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private void updateGrid(int[][] counts) {
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int rows = grid.numRows();
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int cols = grid.numCols();
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for (int r = 0; r < rows; r++) {
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for (int c = 0; c < cols; c++) {
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Cell cell = grid.getCell(r, c);
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updateCell(cell, counts[r][c]);
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}
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}
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}
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/**
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* Simulates one round of Conway's Game of Life.
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*/
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public void update() {
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int[][] counts = countNeighbors();
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updateGrid(counts);
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}
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/**
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* The simulation loop.
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*
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* @param rate frames per second
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*/
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private void mainloop() {
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while (true) {
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// update the drawing
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this.update();
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grid.repaint();
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// delay the simulation
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try {
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Thread.sleep(500);
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} catch (InterruptedException e) {
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// do nothing
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}
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}
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}
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/**
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* Creates and runs the simulation.
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*
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* @param args command-line arguments
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*/
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public static void main(String[] args) {
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String title = "Conway's Game of Life";
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Conway game = new Conway();
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JFrame frame = new JFrame(title);
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frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
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frame.setResizable(false);
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frame.add(game.grid);
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frame.pack();
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frame.setVisible(true);
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game.mainloop();
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}
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}

‎ch15/empty.cells‎

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This file was deleted.

‎ch15/pulsar.cells‎

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This file was deleted.

‎ch16/Automaton.java‎

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@@ -6,8 +6,6 @@
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*/
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public abstract class Automaton {
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public static final int SIZE = 20;
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protected GridCanvas grid;
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/**

‎ch16/Conway.java‎

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Original file line numberDiff line numberDiff line change
@@ -1,80 +1,19 @@
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import java.io.File;
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import java.io.FileNotFoundException;
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import java.util.ArrayList;
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import java.util.Scanner;
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/**
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* Conway's Game of Life.
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*/
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public class Conway extends Automaton {
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/**
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* Creates a grid with a Blinker and a Glider.
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* Creates a grid with two Blinkers.
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*/
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public Conway() {
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grid = new GridCanvas(30, 25, SIZE);
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grid.turnOn(1, 2);
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grid = new GridCanvas(5, 10, 20);
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grid.turnOn(2, 1);
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grid.turnOn(2, 2);
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grid.turnOn(3, 2);
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grid.turnOn(6, 1);
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grid.turnOn(7, 2);
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grid.turnOn(7, 3);
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grid.turnOn(8, 1);
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grid.turnOn(8, 2);
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}
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/**
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* Creates a grid based on a plain text file.
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* http://www.conwaylife.com/wiki/Plaintext
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*
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* @param path the path to the file
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* @param margin how many cells to add
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*/
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public Conway(String path, int margin) {
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// open the file at the given path
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Scanner scan = null;
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try {
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File file = new File(path);
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scan = new Scanner(file);
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} catch (FileNotFoundException e) {
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e.printStackTrace();
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System.exit(1);
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}
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// read file contents into memory
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ArrayList<String> data = new ArrayList<String>();
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while (scan.hasNextLine()) {
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String line = scan.nextLine();
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// only add non-comment lines
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if (!line.startsWith("!")) {
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data.add(line);
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}
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}
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// determine number of rows and columns in the pattern
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int rows = data.size();
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int cols = 0;
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for (String line : data) {
59-
if (cols < line.length()) {
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cols = line.length();
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}
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}
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if (rows == 0 || cols == 0) {
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throw new IllegalArgumentException("no cells found");
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}
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// create the resulting grid with margin of extra cells
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grid = new GridCanvas(rows + 2 * margin, cols + 2 * margin, SIZE);
69-
for (int r = 0; r < rows; r++) {
70-
String line = data.get(r);
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for (int c = 0; c < line.length(); c++) {
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char x = line.charAt(c);
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if (x == 'O') {
74-
grid.turnOn(r + margin, c + margin);
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}
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}
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}
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grid.turnOn(2, 3);
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grid.turnOn(1, 7);
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grid.turnOn(2, 7);
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grid.turnOn(3, 7);
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}
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/**
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*/
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public static void main(String[] args) {
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String title = "Conway's Game of Life";
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Conway game = new Conway("pulsar.cells", 2);
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Conway game = new Conway();
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game.run(title, 2);
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}
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