Question

求走迷宫问题的算法，要求用Java写的？

迷宫是由许多小方格构成的矩形，在每个小方格中有的是墙(“1”)，有的是路(“0”)，以下是一个迷宫示例；走迷宫就是从某一个小方格在不能穿墙时，沿上、下、左、右四个方向走到邻近的方格。设迷宫的入口是在左上角，出口是右下角，根据给定的迷宫，找出任意一条从入口到出口的路径；

Answer 1

public class Maze { private int[][] maze = null;
private int[] xx = { 1, 0, -1, 0 };
private int[] yy = { 0, 1, 0, -1 };
private Queue queue = null; public Maze(int[][] maze) {
this.maze = maze;
queue = new Queue(maze.length * maze.length);
} public void go() {
Point outPt = new Point(maze.length - 1, maze[0].length - 1);
Point curPt = new Point(0, 0);
Node curNode = new Node(curPt, null);
maze[curPt.x][curPt.y] = 2;
queue.entryQ(curNode); while (!queue.isEmpty()) {
curNode = queue.outQ();
for (int i = 0; i < xx.length; ++i) {
Point nextPt = new Point();
nextPt.x = (curNode.point).x + xx[i];
nextPt.y = (curNode.point).y + yy[i];
if (check(nextPt)) {
Node nextNode = new Node(nextPt, curNode);
queue.entryQ(nextNode);
maze[nextPt.x][nextPt.y] = 2;
if (nextPt.equals(outPt)) {
java.util.Stack<Node> stack = new java.util.Stack<Node>();
stack.push(nextNode);
while ((curNode = nextNode.previous) != null) {
nextNode = curNode;
stack.push(curNode);
}
System.out.println("A Path is:");
while (!stack.isEmpty()) {
curNode = stack.pop();
System.out.println(curNode.point);
}
return;
}
}
}
}
System.out.println("Non solution!");
} private boolean check(Point p) {
if (p.x < 0 || p.x >= maze.length || p.y < 0 || p.y >= maze[0].length) {
return false;
}
if (maze[p.x][p.y] != 0) {
return false;
}
return true;
} public static void main(String[] args) {
int[][] maze = {
{ 0, 0, 1, 0, 1, 0, 1, 0, 1, 0 },
{ 0, 0, 1, 1, 1, 0, 0, 0, 1, 0 },
{ 0, 1, 0, 0, 1, 0, 0, 0, 0, 1 },
{ 0, 0, 0, 0, 1, 0, 0, 0, 1, 1 },
{ 0, 0, 1, 0, 0, 0, 0, 0, 0, 1 },
{ 1, 0, 1, 0, 1, 0, 0, 1, 0, 0 },
{ 0, 1, 0, 0, 1, 0, 0, 1, 0, 1 },
{ 1, 0, 1, 0, 1, 1, 0, 1, 0, 0 }
};
new Maze(maze).go();
} private class Queue { Node[] array = null;
int size = 0;
int len = 0;
int head = 0;
int tail = 0; public Queue(int n) {
array = new Node[n + 1];
size = n + 1;
} public boolean entryQ(Node node) {
if (isFull()) {
return false;
}
tail = (tail + 1) % size;
array[tail] = node;
len++;
return true;
} public Node outQ() {
if (isEmpty()) {
return null;
}
head = (head + 1) % size;
len--;
return array[head];
} public boolean isEmpty() {
return (len == 0 || head == tail) ? true : false;
} public boolean isFull() {
return ((tail + 1) % size == head) ? true : false;
}
} private class Node { Point point = null;
Node previous = null; public Node() {
this(null,null);
} public Node(Point point, Node node) {
this.point = point;
this.previous = node;
}
} private class Point { int x = 0;
int y = 0; public Point() {
this(0, 0);
} public Point(int x, int y) {
this.x = x;
this.y = y;
} public boolean equals(Point p) {
return (x == p.x) && (y == p.y);
} @Override
public String toString() {
return "(" + x + "," + y + ")";
}
}
}