Java简易撞鬼游戏demo

9*9方格内两点随机行走，相遇则停止。

public class 撞鬼 {

    public static int length = 9;
    public static char[][] matrix = new char[length][length];
    public static int firstx = length - length;
    public static int firsty = length - length;
    public static int secondx = length - 1;
    public static int secondy = length - 1;
    
    public static void main(String[] args) {
        
        final int timeInterval = 333;
        
        for(int i=length - length;i<length;i++){
            for(int j=length - length;j<length;j++){
                matrix[i][j] = '○';
                if((i==j&&i==(length - length))||(i==j&&i==(length-1))){
                    matrix[i][j] = '●';
                }
            }
        }
        
        Runnable runnable = new Runnable() {
            public void run() {
                while (true) {
                    try {
                        for(int i=length - length;i<length;i++){
                            for(int j=length - length;j<length;j++){
                                System.out.print(matrix[i][j]);
                                System.out.print(' ');
                            }
                            System.out.println();
                        }
                        if(firstx==secondx&&firsty==secondy){
                            break;
                        }
                        changePosition();
                        Thread.sleep(timeInterval);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            }
        };
        Thread thread = new Thread(runnable);
        thread.start();
        
    }
    
    public static void changePosition(){
        double randomfirst = Math.random();
        double randomsecond = Math.random();
        if(randomfirst<0.25){
            if(firstx>length - length){
                matrix[firstx--][firsty] = '○';
                matrix[firstx][firsty] = '●';
            }
        }else if(randomfirst<0.50){
            if(firstx<length - 1){
                matrix[firstx++][firsty] = '○';
                matrix[firstx][firsty] = '●';
            }
        }else if(randomfirst<0.75){
            if(firsty>length - length){
                matrix[firstx][firsty--] = '○';
                matrix[firstx][firsty] = '●';
            }
        }else{
            if(firsty<length - 1){
                matrix[firstx][firsty++] = '○';
                matrix[firstx][firsty] = '●';
            } 
        }
        if(randomsecond<0.25){
            if(secondx>length - length){
                matrix[secondx--][secondy] = '○';
                matrix[secondx][secondy] = '●';
            }
        }else if(randomsecond<0.50){
            if(secondx<length - 1){
                matrix[secondx++][secondy] = '○';
                matrix[secondx][secondy] = '●';
            }
        }else if(randomsecond<0.75){
            if(secondy>length - length){
                matrix[secondx][secondy--] = '○';
                matrix[secondx][secondy] = '●';
            }
        }else{
            if(secondy<length - 1){
                matrix[secondx][secondy++] = '○';
                matrix[secondx][secondy] = '●';
            } 
        }
    }
        
}