import java.io.*;

public class exp		// a class for timing experiments
{  
   private int[] A;

//  Create Test Data File:    
public void make_data(int nums, String filename)
{ int i;
  RandomAccessFile outfile;
  try {	// must encapsulate IO
     outfile = new RandomAccessFile(filename, "rw");
     for (i=0;i<nums;i++) 
         outfile.writeInt( (int) (Math.random() * 10000) );
     outfile.close();
       } 
   catch (IOException e) {System.out.println("file IO Error!");}
}

// Fills array A from file
public void read_data(int size, String filename) 	

  { RandomAccessFile infile;
    A = new int[size]; 
    /*  Read numers from file to array */ 
    try {	// must encapsulate IO
     	  infile = new RandomAccessFile(filename, "r");
    	   for (int i=0;i<size;i++) 
             A[i] = infile.readInt();
       	  infile.close();
       } 
    catch (IOException e) {System.out.println("file IO Error!");} 
  }  // end of constructor

public void print()			// prints array A
  { for(int i=0;i<A.length;i++)
      System.out.print(A[i] + " ");
    System.out.println("");
  }

public int findmax()			// finds largest integer in A
  { int max = 0;
    int i;
    for (i=0;i<A.length;i++)
      if (A[i] > max) max = A[i];
    return max;
  }

public void bubblesort()		// classic bubble sort algorithm
  { int i, j, temp;
    for(i=0;i<A.length - 1;i++)
      for(j=0;j<A.length - 1 - i;j++)
        if (A[j] > A[j+1])
          	{ temp = A[j];
          	  A[j] = A[j+1];
          	  A[j+1] = temp;
          	}
  }

public static void main(String[] args)
  {  int i, j, max;
     long StartTime, ElapseTime, st2, et2;	// not 'long'
     int nums = 1000;   	// change this to alter array size
     String file; 		// file name
     exp exp0;     		// the experiment object
     file = "nums" + nums;  	// file name is dependent on array size
   
     exp0 = new exp();		// create experiment object

     exp0.make_data(nums,file);            // uncomment to make data file.
     exp0.read_data(nums,file);
     	      
     StartTime = System.currentTimeMillis();
     exp0.bubblesort();	// find the maximum number
     ElapseTime = System.currentTimeMillis() - StartTime;

     st2 = System.currentTimeMillis();
     exp0.print();	// print the array
     et2 = System.currentTimeMillis() - st2;
     
     System.out.println("Approximate time for bubblesort = " + 
     					 ElapseTime + " milliseconds.");     
     System.out.println("Approximate time to print = " + 
     					 et2 + " milliseconds.");
     
     try {System.in.read();} catch (IOException e) {}  // needed for PC's
  }
    
  
}