Time,movement,comparison for Bubble,Selection,Insertion sort

package sorted;

import java.util.Random;

public class Main
{
    static int[] firstArray = new int[20001];
    static int[] secondArray = new int[20001];
    static int i, j, k, temporary, comparison, interchange, t;


    static void selection_sort()
    {
        for(i=1; i<=20000; i++)
        {
            secondArray[i]=firstArray[i];
        }

        secondArray[0]=Integer.MIN_VALUE;
        interchange=0;
        comparison=0;
        long started = System.nanoTime();
        for(j=20000; j>0; j--)
        {
            t=0;
            for(k=2; k<=j; k++)
            {
                comparison=comparison+1;
                if(secondArray[t]<secondArray[k])
                {
                    t=k;
                }
            }
            temporary=secondArray[j];
            secondArray[j]=secondArray[t];
            secondArray[t]=temporary;
            interchange=interchange+1;
        }
        long finished = System.nanoTime()-started;

        System.out.print("Selection         "+finished*1e-6+" millisecond       "+interchange+"                 "+comparison+"\n");
    }

    static void insertion_sort()
    {
        for(i=1; i<=20000; i++)
        {
            secondArray[i]=firstArray[i];
        }
        secondArray[0]=Integer.MIN_VALUE;
        comparison=0;
        interchange=0;
        long started = System.nanoTime();
        for(j=2; j<=20000; j++)
        {
            i=j-1;
            temporary=secondArray[j];
            comparison=comparison+1;
            while(temporary<secondArray[i])
            {
                interchange=interchange+1;
                secondArray[i+1]=secondArray[i];
                i=i-1;
                comparison=comparison+1;
            }
            secondArray[i+1]=temporary;
        }
        long finished = System.nanoTime()-started;

        System.out.print("Insertion         "+finished*1e-6+" millisecond       "+interchange+"                 "+comparison+"\n");
    }

    static void bubble_sort()
    {
        for(i=1; i<=20000; i++)
        {
            secondArray[i]=firstArray[i];
        }
        secondArray[0]=Integer.MIN_VALUE;
        comparison=0;
        interchange=0;
        long started = System.nanoTime();
        k=20000;

        while(k!=0)
        {
            t=0;
            for(j=1; j<= k-1; j++)
            {
                comparison=comparison+1;
                if(secondArray[j]>secondArray[j+1])
                {
                    temporary=secondArray[j];
                    secondArray[j]=secondArray[j+1];
                    secondArray[j+1]=temporary;
                    t=j;
                    interchange=interchange+1;
                }
            }
            k=t;
        }
        long finished = System.nanoTime()-started;

        System.out.print("Bubble            "+finished*1e-6+" millisecond       "+interchange+"                 "+comparison+"\n");
    }

    public static void main(String[] args)
    {
        Random random = new Random();
        for(i=1; i<=20000; i++)
        {
            firstArray[i]=random.nextInt();
        }
        System.out.print("Sort              \tTime                  \tMovement              \tComparison\n");
        selection_sort();
        insertion_sort();
        bubble_sort();
    }
}