1 files changed, 104 insertions, 0 deletions
diff --git a/src/main/java/me/Danker/utils/SilverfishUtils.java b/src/main/java/me/Danker/utils/SilverfishUtils.java
new file mode 100644
index 0000000..e495da5
--- /dev/null
+++ b/src/main/java/me/Danker/utils/SilverfishUtils.java
@@ -0,0 +1,104 @@
+package me.Danker.utils;
+
+import java.util.*;
+
+public class SilverfishUtils {
+
+    // bfs
+    public static List<Point> solve(char[][] board, Point startPos, List<Point> endColumns) {
+        LinkedList<Point> queue = new LinkedList<>();
+        Map<Point, Point> visited = new HashMap<>();
+        queue.add(startPos);
+        visited.put(startPos, null);
+        while (!queue.isEmpty()) {
+            if (queue.size() > 1000000) break;
+            Point position = queue.pollFirst();
+            for (Direction direction : Direction.values()) {
+                Point pushedPoint = push(board, position, direction);
+                if (visited.containsKey(pushedPoint)) continue;
+                queue.add(pushedPoint);
+                visited.put(pushedPoint, position);
+                for (Point endColumn : endColumns) {
+                    if (pushedPoint.equals(endColumn)) {
+                        List<Point> route = new ArrayList<>();
+                        Point lastPoint = pushedPoint;
+                        while (lastPoint != null) {
+                            route.add(0, lastPoint);
+                            lastPoint = visited.get(lastPoint);
+                        }
+                        return route;
+                    }
+                }
+            }
+        }
+        return new ArrayList<>();
+    }
+
+    public static Point push(char[][] board, Point pos, Direction direction) {
+        switch (direction) {
+            case UP:
+                for (int row = pos.row; row >= 0; row--) {
+                    if (board[row][pos.column] == 'X') {
+                        return new Point(row + 1, pos.column);
+                    }
+                }
+                return new Point(0, pos.column);
+            case DOWN:
+                for (int row = pos.row; row <= 18; row++) {
+                    if (board[row][pos.column] == 'X') {
+                        return new Point(row - 1, pos.column);
+                    }
+                }
+                return new Point(18, pos.column);
+            case LEFT:
+                for (int column = pos.column; column >= 0; column--) {
+                    if (board[pos.row][column] == 'X') {
+                        return new Point(pos.row, column + 1);
+                    }
+                }
+                return new Point(pos.row, 0);
+            case RIGHT:
+                for (int column = pos.column; column <= 18; column++) {
+                    if (board[pos.row][column] == 'X') {
+                        return new Point(pos.row, column - 1);
+                    }
+                }
+                return new Point(pos.row, 18);
+        }
+        return null;
+    }
+
+    public static class Point {
+
+        public int row;
+        public int column;
+
+        public Point(int row, int column) {
+            this.row = row;
+            this.column = column;
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(row, column);
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (obj instanceof Point) {
+                Point point = (Point) obj;
+                return row == point.row && column == point.column;
+            }
+            return false;
+        }
+
+    }
+
+    enum Direction {
+        UP,
+        DOWN,
+        LEFT,
+        RIGHT
+    }
+
+}