Chapter 12, Problem 20E

Explanation of Solution

Program:

//Import required packages

import java.util.Stack;

//Definition of class Test

public class Test

{

    //Declare the variable

    public int top;

    //Definition of main method

    public static void main(String[] args) {

        //Call the method

        waysToClimb(4);

    }

    //Definition of method waysToClimb()

    public static void waysToClimb(int stairs)

    {

        //Create an object for stack

        Stack<Integer> value = new Stack<Integer>();

        //Call the recursive method waysToClimn()

        waysToClimb(stairs, value);

    }

    //Definition of method waysToClimn

private static void waysToClimb(int stairs, Stack<Integer> value)

    {

        //Check whether the staris less than or equal to 0

        if (stairs <= 0)

        {

            //Print the value

            System.out.println(value);

        }

        //Otherwise

        else {

            //Push the value to the stack

            value.push(1);

            //Call the recursive method waysToClimb

            waysToClimb(stairs - 1, value);

            //Pop the value from the stack

            value...