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Maze.java
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Maze.java
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import java.awt.Point;
import java.io.File;
import java.io.FileNotFoundException;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.Scanner;
public class Maze {
private static char[][] maze;
private static final int[][] dir = { { -1, 0, 0, 1 }, { 0, -1, 1, 0 } };
private static boolean isValid(int x, int y) {
return x >= 0 && x < maze.length && y >= 0 && y < maze[0].length;
}
private static void backTrack(HashMap<Point, Point> visit, Point pt) {
while (pt != null) {
if (maze[pt.x][pt.y] == ' ') // TODO
maze[pt.x][pt.y] = 'X'; // TODO
pt = visit.get(pt);
}
}
private static void floodFill(Point start, Point end) {
LinkedList<Point> bfs = new LinkedList<>();
HashMap<Point, Point> visit = new HashMap<>();
bfs.add(start);
visit.put(start, null);
A: while (!bfs.isEmpty()) {
Point pt = bfs.poll();
for (int i = 0; i < dir[0].length; i++) {
int x = pt.x + dir[0][i];
int y = pt.y + dir[1][i];
Point adj = new Point(x, y);
if (end.equals(adj)) {
visit.put(end, pt);
break A;
}
if (isValid(x, y) && maze[x][y] == ' ' // TODO
&& !visit.containsKey(adj)) {
bfs.add(adj);
visit.put(adj, pt);
}
}
}
backTrack(visit, end);
}
public static void main(String[] args) throws FileNotFoundException {
Scanner scan = new Scanner(new File(".txt"));
int n = scan.nextInt();
for (int i = 0; i < n; i++) {
maze = new char[10][]; // TODO
Point start = null, end = null;
for (int j = 0; j < maze.length; j++) {
maze[j] = scan.next().toCharArray();
for (int k = 0; k < maze[j].length; k++) {
if (maze[j][k] == 'S') // TODO
start = new Point(j, k);
else if (maze[j][k] == 'E') // TODO
end = new Point(j, k);
}
}
floodFill(start, end);
for (char[] c : maze)
System.out.println(new String(c));
System.out.println();
}
scan.close();
}
}