动态规划——走迷宫

package OJ;

import java.util.*;

import java.util.regex.Matcher;

public class Bully {

/*
* 动态规划
* 走迷宫
* 1不能走，0可以走

* */

private static int[][] graph = {{0,1,1,0,0},{0,1,1,0,0},{0,1,0,0,0},{0,0,0,1,0},{1,1,0,1,0}};
private static int n = graph.length;

private static StringBuffer sb = new StringBuffer();

private static ArrayList<String> al = new ArrayList<String>();

public static void main(String[] args) {

getOutFromHere(0,0,sb,new int

);

sop(al);
sop(al.size());
}

private static void getOutFromHere(int i, int j, StringBuffer path,int[][] visit) {

visit[i][j] = 1;  //建立的一个访问表，已访问为1
path.append(i+""+j+" ");

if(i==n-1 && j==n-1){
al.add(path.toString());
}else{
if(i+1<n){  //向下移动
if(graph[i+1][j]==0 && visit[i+1][j]==0){
getOutFromHere(i+1,j,path,visit);
}
}
if(j+1<n){
//向右移动
if(graph[i][j+1]==0 && visit[i][j+1]==0){
getOutFromHere(i,j+1,path,visit);
}
}
if(i-1>=0){
//向上移动
if(graph[i-1][j]==0 && visit[i-1][j]==0){
getOutFromHere(i-1,j,path,visit);
}
}
if(j-1>=0){
//向左移动
if(graph[i][j-1]==0 && visit[i][j-1]==0){
getOutFromHere(i,j-1,path,visit);
}
}
}
//四个方向都不能走，那么退回来
visit[i][j] = 0;
path.setLength(path.length()-1-String.valueOf(i).length()-String.valueOf(j).length());

}

public static void sop(Object o){
System.out.println(o);
}

}