Algorithm-Percolation-code

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初步Percolation的代码，用0和1代表方格，1为打开，0为关闭，代码中会显示导通（Percolate）时的图形和各个点的根节点（根结点参照WeightedQuickUnionUF算法）
package percolation;import edu.princeton.cs.algs4.*;import java.util.*;import java.util.Random;public class Percolation {    private int[] status;    private int N;    private int row,col;    WeightedQuickUnionUF m;    public Percolation(int n)   //初始化数组，每个格子表示符为自己的顺序    {        this.status = new int[n*n];        this.N = n;        m = new WeightedQuickUnionUF(N*N);    }    public void open (int row, int col)      //打开格子    {//      System.out.printf("open row:%d col:%d\n",row,col);//      System.out.println("open site:"+(row*N+col));        this.status[row*N+col] = 1;        this.row = row;        this.col = col;    }    int setRC(int i)    {        if(i<0) return 0;        else    if(i>N-1) return N-1;        else return i;    }    public boolean isOpen(int row, int col) //格子是打开的    {        if(this.status[row*N+col] == 1)        {            return true;        }        else return false;    }    public boolean isFull(int row, int col) //格子是关闭的    {        if(this.status[row*N+col] == 0)        {            return true;        }        else return false;    }    public void display()    {        System.out.println("###########root start############");        for(int i=0;i<N;i++)        {            for(int j=0;j<N;j++)            {                System.out.print(this.m.find(i*N+j)+" ");            }            System.out.printf("\n");        }        System.out.println("#########root end#######");        System.out.println("#########status start#######");        for(int i=0;i<N;i++)        {            for(int j=0;j<N;j++)            {                System.out.print(this.status[i*N+j]+" ");            }            System.out.printf("\n");        }        System.out.println("#########status end#######");    }//  public boolean is    public boolean percolates() //检查是否联通            //断点记录：判断新增的格子周围的格子是否是空的，如果是，则联通    {        if  (this.isOpen(setRC(row-1),col))   m.union(row*N+col, setRC(row-1)*N+col);        if  (this.isOpen(setRC(row+1),col))   m.union(row*N+col, setRC(row+1)*N+col);        if  (this.isOpen(row,setRC(col+1)))   m.union(row*N+col, row*N+setRC(col+1));        if  (this.isOpen(row,setRC(col-1)))   m.union(row*N+col, row*N+setRC(col-1));        for (int i=0;i<N;i++)       //判断是否导通        {               int tmp = this.m.find(i);            for(int j=0;j<N;j++)            {                if(tmp == this.m.find(N*(N-1)+j))                {                    System.out.println("root is "+tmp);                    return true;                }            }        }        return false;    }    public static void main(String[] args) {        int n = 200;        int repeat = 100;        int count_in = 0;        int count_out = 0;        Random random  = new Random();        for(int i=0;i<repeat;i++)        {               Percolation a = new Percolation(n);            while(true)            {                int row= random.nextInt(n);                int col = random.nextInt(n);                if(a.isOpen(row, col))                          {                    continue;                }                a.open(row, col);                count_in++;                 if(a.percolates())                {                    break;                }            }            a.display();            System.out.println("count_in:"+count_in);            count_out +=count_in;            count_in = 0;            System.out.println("count_out:"+count_out);        }        System.out.println("count_out:"+count_out);        System.out.println((float)count_out/(n*n*repeat));    }}
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