hi i have following question from book introduction in algorithms second edition there is such problem suppose we have some array A

int a[]={1,2,3,4}  and we have some random priorities array
P={36,3,97,19}  we shoud permut   array a randomly using  this priorities array

here is pseudo code

P ERMUTE -B Y-S ORTING ( A)
1 n ? length[A]
2 for i ? 1 to n
       do P[i] = R ANDOM(1, n 3 )
3
4 sort A, using P as sort keys
5 return A

and result will be permuted array

B={2, 4, 1, 3};

please help any ideas

i have done this code and need aideas how continue

import java.util.*;
public class Permut {


public static void main(String[]args){

Random r=new Random();
int a[]=new int[]{1,2,3,4};
int n=a.length;
  int b[]=new int[a.length];
int p[]=new int[a.length];
 for (int i=0;i<p.length;i++){
 p[i]=r.nextInt(n*n*n)+1;
}

// for (int i=0;i<p.length;i++){
 // System.out.println(p[i]);
//}


}
}

please help