gradle/wrapper/gradle-wrapper.properties

 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.4-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.10.2-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

src/main/java/app/SimulatorApplication.java

@@ -26,7 +26,7 @@ public class SimulatorApplication extends javafx.application.Application {
     this.primaryStage = primaryStage;
     this.primaryStage.setTitle(APP_NAME);
     this.primaryStage.setOnCloseRequest(event -> Platform.exit());
-    this.primaryStage.setResizable(false);
+    this.primaryStage.setResizable(true);
     this.primaryStage.sizeToScene();
   }
 

src/main/java/model/FirefighterBoard.java

@@ -10,14 +10,30 @@ public class FirefighterBoard implements Board<List<ModelElement>> {
   private final int rowCount;
   private final int initialFireCount;
   private final int initialFirefighterCount;
+  private final TargetStrategy targetStrategy = new TargetStrategy();
   private List<Position> firefighterPositions;
   private Set<Position> firePositions;
+  private Map<Position, List<Position>> neighbors = new HashMap();
+  private final Position[][] positions;
   private int step = 0;
   private final Random randomGenerator = new Random();
 
   public FirefighterBoard(int columnCount, int rowCount, int initialFireCount, int initialFirefighterCount) {
     this.columnCount = columnCount;
     this.rowCount = rowCount;
+    this.positions = new Position[rowCount][columnCount];
+    for (int column = 0; column < columnCount; column++)
+      for (int row = 0; row < rowCount; row++)
+        positions[row][column] = new Position(row, column);
+    for (int column = 0; column < columnCount; column++)
+      for (int row = 0; row < rowCount; row++) {
+        List<Position> list = new ArrayList<>();
+        if (row > 0) list.add(positions[row - 1][column]);
+        if (column > 0) list.add(positions[row][column - 1]);
+        if (row < rowCount - 1) list.add(positions[row + 1][column]);
+        if (column < columnCount - 1) list.add(positions[row][column + 1]);
+        neighbors.put(positions[row][column], list);
+      }
     this.initialFireCount = initialFireCount;
     this.initialFirefighterCount = initialFirefighterCount;
     initializeElements();
@@ -58,23 +74,23 @@ public class FirefighterBoard implements Board<List<ModelElement>> {
   }
 
   public List<Position> updateToNextGeneration() {
-    List<Position> result = updateFirefighters();
-    result.addAll(updateFires());
+    List<Position> modifiedPositions = updateFirefighters();
+    modifiedPositions.addAll(updateFires());
     step++;
-    return result;
+    return modifiedPositions;
   }
 
   private List<Position> updateFires() {
-    List<Position> result = new ArrayList<>();
+    List<Position> modifiedPositions = new ArrayList<>();
     if (step % 2 == 0) {
       List<Position> newFirePositions = new ArrayList<>();
       for (Position fire : firePositions) {
-        newFirePositions.addAll(neighbors(fire));
+        newFirePositions.addAll(neighbors.get(fire));
       }
       firePositions.addAll(newFirePositions);
-      result.addAll(newFirePositions);
+      modifiedPositions.addAll(newFirePositions);
     }
-    return result;
+    return modifiedPositions;
 
   }
 
@@ -84,22 +100,24 @@ public class FirefighterBoard implements Board<List<ModelElement>> {
   }
 
   private List<Position> updateFirefighters() {
-    List<Position> result = new ArrayList<>();
+    List<Position> modifiedPosition = new ArrayList<>();
     List<Position> firefighterNewPositions = new ArrayList<>();
     for (Position firefighterPosition : firefighterPositions) {
-      Position newFirefighterPosition = neighborClosestToFire(firefighterPosition);
+      Position newFirefighterPosition =
+              targetStrategy.neighborClosestToFire(firefighterPosition,
+                      firePositions, neighbors);
       firefighterNewPositions.add(newFirefighterPosition);
       extinguish(newFirefighterPosition);
-      result.add(firefighterPosition);
-      result.add(newFirefighterPosition);
-      List<Position> neighborFirePositions = neighbors(newFirefighterPosition).stream()
+      modifiedPosition.add(firefighterPosition);
+      modifiedPosition.add(newFirefighterPosition);
+      List<Position> neighborFirePositions = neighbors.get(newFirefighterPosition).stream()
               .filter(firePositions::contains).toList();
       for (Position firePosition : neighborFirePositions)
         extinguish(firePosition);
-      result.addAll(neighborFirePositions);
+      modifiedPosition.addAll(neighborFirePositions);
     }
     firefighterPositions = firefighterNewPositions;
-    return result;
+    return modifiedPosition;
   }
 
   @Override
@@ -112,34 +130,6 @@ public class FirefighterBoard implements Board<List<ModelElement>> {
     firePositions.remove(position);
   }
 
-  private List<Position> neighbors(Position position) {
-    List<Position> list = new ArrayList<>();
-    if (position.row() > 0) list.add(new Position(position.row() - 1, position.column()));
-    if (position.column() > 0) list.add(new Position(position.row(), position.column() - 1));
-    if (position.row() < rowCount - 1) list.add(new Position(position.row() + 1, position.column()));
-    if (position.column() < columnCount - 1) list.add(new Position(position.row(), position.column() + 1));
-    return list;
-  }
-
-  private Position neighborClosestToFire(Position position) {
-    Set<Position> seen = new HashSet<>();
-    HashMap<Position, Position> firstMove = new HashMap<>();
-    Queue<Position> toVisit = new LinkedList<>(neighbors(position));
-    for (Position initialMove : toVisit)
-      firstMove.put(initialMove, initialMove);
-    while (!toVisit.isEmpty()) {
-      Position current = toVisit.poll();
-      if (firePositions.contains(current))
-        return firstMove.get(current);
-      for (Position adjacent : neighbors(current)) {
-        if (seen.contains(adjacent)) continue;
-        toVisit.add(adjacent);
-        seen.add(adjacent);
-        firstMove.put(adjacent, firstMove.get(current));
-      }
-    }
-    return position;
-  }
 
   @Override
   public void setState(List<ModelElement> state, Position position) {

src/main/java/util/TargetStrategy.java

+package model;
+
+import util.Position;
+
+import java.util.*;
+
+public class TargetStrategy {
+
+
+    /**
+     * @param position current position.
+     * @param targets positions that are targeted.
+     * @return the position next to the current position that is on the path to the closest target.
+     */
+    Position neighborClosestToFire(Position position, Collection<Position> targets,
+                                   Map<Position,List<Position>>neighbors) {
+        Set<Position> seen = new HashSet<Position>();
+        HashMap<Position, Position> firstMove = new HashMap<Position, Position>();
+        Queue<Position> toVisit = new LinkedList<Position>(neighbors.get(position));
+        for (Position initialMove : toVisit)
+            firstMove.put(initialMove, initialMove);
+        while (!toVisit.isEmpty()) {
+            Position current = toVisit.poll();
+            if (targets.contains(current))
+                return firstMove.get(current);
+            for (Position adjacent : neighbors.get(current)) {
+                if (seen.contains(adjacent)) continue;
+                toVisit.add(adjacent);
+                seen.add(adjacent);
+                firstMove.put(adjacent, firstMove.get(current));
+            }
+        }
+        return position;
+    }
+}
\ No newline at end of file