SelfAvoidingWalk.java pgm

SelfAvoidingWalk.java

public class SelfAvoidingWalk 

{

 public static void main(String[] args) 

{

        int N = Integer.parseInt(args[0]);       

        int T = Integer.parseInt(args[1]);       

        int deadEnds = 0;                        

                        for (int t = 0; t < T; t++) 

            {

            boolean[][] a = new boolean[N][N];   

            int x = N/2, y = N/2;                

                         while (x > 0 && x < N-1 && y > 0 && y < N-1)  

            {

            if (a[x-1][y] && a[x+1][y] && a[x][y-1] && a[x][y+1])

             {

                    deadEnds++;

                    break;

                } 

                a[x][y] = true; 

                double r = Math.random(); 

                if      (r < 0.25) { if (!a[x+1][y]) x++; 

                }

                else if (r < 0.50) { if (!a[x-1][y]) x--; 

                }

                else if (r < 0.75) { if (!a[x][y+1]) y++; 

                }

                else if (r < 1.00) { if (!a[x][y-1]) y--; 

                }

            } 

        } 

        System.out.println(100*deadEnds/T + "% dead ends"); 

    } 

}