how to write this program,what are the declaration and function are needed in java

program in java

// aakash , suraj , prem sasi kumar kamaraj college
program 1 :

Program set 2 :

import java.util.Scanner;

import java.util.ArrayList;

public class PadovanSeries

{

    public static void main(String[] arg)

    {

        Scanner read = new Scanner(System.in);

        System.out.println("Enter starting no. : ");

        int start = read.nextInt();

        System.out.println("Enter ending no. : ");

        int end = read.nextInt();

        int[] ans = getSeries(start, end);

        System.out.println("Padovan series : ");

        for (int a : ans)

            System.out.print(a + " ");

    }

    public static int[] getSeries(int s, int e)

    {

        ArrayList list = new ArrayList();

        int i, j = 0;

        for (i = s; i <= e; i++, j++)

            list.add(getPadovan(i));

        int[] ans = new int[j];

        for (i = 0; i < j; i++)

            ans[i] = list.get(i);

        return ans;

    }

    public static int getPadovan(int p)

    {

        if (p == 0 || p == 1 || p == 2)

            return 1;

        return (getPadovan(p - 2) + getPadovan(p - 3));

    }

}

Padova