Chapter 4 Reference Answers

Questions
1. b 7. c 13. a
2. c 8. d 14. b
3. d 9. a 15. b
4. b 10. d 16. c
5. b 11. c 17. c
6. a 12. d 18. a

Exercises
1a.
// Password.java
// Chapter 4, Section A, Exercise 1a
public class Password {
    public static void main (String[] args) throws Exception {
        char p1, p2, p3, p4;
        System.out.println("Please enter a " +
            "four-character \npassword, and press Enter when done:");
        p1 = (char)System.in.read();
        p2 = (char)System.in.read();
        p3 = (char)System.in.read();
        p4 = (char)System.in.read();
        System.out.println("Your password is: "
                    + p1 + p2 + p3 + p4);
    }
}

1b.
// Password2.java
// Chapter 4, Section A, Exercise 1b
public class Password2 {
    public static void main (String[] args) throws Exception    {
        char p1, p2, p3, p4;
        System.out.println("Please enter a four-character " +
                            "\npassword, and press Enter when done:");
        p1 = (char)System.in.read();
        p2 = (char)System.in.read();
        p3 = (char)System.in.read();
        p4 = (char)System.in.read();
        System.out.println("Your password is: "
                            + p1 + p2 + p3 + p4);
        if (p1 == 'B')
            System.out.println("Valid password");
        else
            System.out.println("Invalid password");
    }
}
1c.
// Password3.java
// Chapter 4, Section A, Exercise 1c
public class Password3    {
    public static void main (String[] args) throws Exception    {
        char p1, p2, p3, p4;
        boolean passTest = true;
        System.out.println("Please enter a four-character " +
                            "\npassword, and press Enter when done:");
        p1 = (char)System.in.read();
        p2 = (char)System.in.read();
        p3 = (char)System.in.read();
        p4 = (char)System.in.read();
        System.out.println("Your password is: "
                            + p1 + p2 + p3 + p4);
        if (p1 != 'B')
            passTest = false;
        if (p2 != 'O')
            passTest = false;
        if (p3 != 'L')
            passTest = false;
        if (p4 != 'T')
            passTest = false;
        if (passTest == true)
            System.out.println("Valid password");
        else
            System.out.println("Invalid password");
    }
}
2a.
// Furniture.java
// Chapter 4, Section A, Exercise 2a
public class Furniture {
    public static void main (String[] args) throws Exception {
        char selection;
        System.out.println("\tMenu\n\n\tPine (P)\n\tOak (O)\n\tMahogany (M)");
        System.out.print("\n\n\tEnter Selection (P, O, M): ");
        selection = (char)System.in.read();
        if (selection == 'P')
            System.out.println("\nPine table cost is $100");
        else if (selection == 'O')
            System.out.println("\nOak table cost is $225");
        else if (selection == 'M')
            System.out.println("\nMahogany table cost is $310");
        else
            System.out.println("\nInvalid Selection...");
    }
}
2b.
// FurnitureSizes.java
// Chapter 4, Section A, Exercise 2b
public class FurnitureSizes {
    public static void main (String[] args) throws Exception {
        char selection;
        char size;
        System.out.println("\tMenu\n\n\tPine (P)\n\tOak (O)\n\tMahogany (M)");
        System.out.print("\n\n\tEnter Selection (P, O, M): ");
        selection = (char)System.in.read();
        // discard the Enter key
        System.in.read();
        System.in.read();
        System.out.print("\n\nEnter Size, Large (L), Small (S): ");

        size = (char)System.in.read();
        // check type and size, use small for size for default
        if (selection == 'P') {
            System.out.print("\nPine table cost is ");
            if (size == 'L')
                System.out.println("$135");
            else
                System.out.println("$100");
        }
        if (selection == 'O') {
            System.out.print("\nOak table cost is ");
            if (size == 'L')
                System.out.println("$260");
            else
                System.out.println("$225");
        }
        if (selection == 'M') {
            System.out.print("\nMahogany table cost is ");
            if (size == 'L')
                System.out.println("$345");
            else
                System.out.println("$310");
        }
        else
            System.out.println("\nInvalid Selection...");
    }
}
3.
// Admission.java
// Chapter 4, Section A, Exercise 3
public class Admission    {
    public static void main (String[] args) throws Exception {
        double gpa = 3.5;
        int score = 59;
        System.out.println("The Grade Point Average is " + gpa);
        System.out.println("The Score is " + score);
        if ((score >= 80) || (gpa >= 3.0 && score >= 60))
            System.out.println("Accept");
        else
            System.out.println("Reject");
    }
}

4.
// Payroll.java
// Chapter 4, Section A, Exercise 4
public class Payroll {
    public static void main (String[] args) throws Exception {
        double hourlyRate = 25;
        double hoursWorked = 40;
        double withholdingTax;
        double pctTax;
        double grossPay = hourlyRate * hoursWorked;
        
        if (grossPay > 300.00)
            pctTax = .12;
        else
            pctTax = .10;
        withholdingTax = grossPay * pctTax;
        System.out.println("The gross pay for "
                            + hoursWorked + " hours worked"
                            + " at a rate of " + hourlyRate + " per hour is "
                            + grossPay + "\nThe net pay is "
                            + (grossPay - withholdingTax)
                            + " based on tax rate of " + pctTax);
    }
}
5a.
// Calculate.java
// Chapter 4, Section A, Exercise 5a
public class Calculate {
    public static void main (String[] args) throws Exception {
        char selection;
        int number1 = 18;
        int number2 = 5;
        System.out.print("Enter A(dd), S(ubtract), M(ultiply): ");
        selection = (char)System.in.read();
        if (selection == 'A')
            System.out.println(number1 + " plus "
                            + number2 + " = " + (number1 + number2));
        else if (selection == 'S')
            System.out.println(number1 + " minus "
                            + number2 + " = " + (number1 - number2));
        else if (selection == 'M')
            System.out.println(number1 + " times "
                            + number2 + " = " + (number1 * number2));
        else
            System.out.println("\nInvalid Selection...");
    }
}
5b.
// Calculate2.java
// Chapter 4, Section A, Exercise 5b
public class Calculate2 {
    public static void main (String[] args) throws Exception {
        char selection;
        int number1 = 18;
        int number2 = 0;
        System.out.print("Enter A(dd), S(ubtract), M(ultiply), D(ivide): ");
        selection = (char)System.in.read();
        if (selection == 'A')
            System.out.println(number1 + " plus "
                        + number2 + " = " + (number1 + number2));
        else if (selection == 'S')
            System.out.println(number1 + " minus "
                        + number2 + " = " + (number1 - number2));
        else if (selection == 'M')
            System.out.println(number1 + " times "
                        + number2 + " = " + (number1 * number2));
        else if (selection == 'D')
            if (number2 == 0)
                System.out.println("Divide by zero error...");
            else
                System.out.println(number1 + " divided by "
                                + number2 + " = " + (number1 / number2));
            else
                System.out.println("\nInvalid Selection...");
    }
}
6a.
// Lawn.java
// Chapter 4, Section A, Exercise 6a
public class Lawn {
    public static void main (String[] args) throws Exception {
        int length = 10, width = 54;
        int lotSize = length * width;
        int weeklyFee;
        
        if (lotSize < 400)
            weeklyFee = 25;
        else if (lotSize < 600)
            weeklyFee = 35;
        else
            weeklyFee = 50;
        System.out.println("The your payment for a lot of "
                + lotSize + " square feet is "
                + weeklyFee + " per week or "
                + (weeklyFee * 20) + " seasonal fee");
    }
}
6b.
// Lawn2.java
// Chapter 4, Section A, Exercise 6b
public class Lawn2 {
    public static void main (String[] args) throws Exception {
        int length = 10, width = 54;
        int lotSize = length * width;
        int weeklyFee;
        char selection;
        
        if (lotSize < 400)
            weeklyFee = 25;
        else if (lotSize < 600)
            weeklyFee = 35;
        else
            weeklyFee = 50;
        System.out.println("\tMenu\n\n\tOne Payment (A)" +
                        "\n\tTwo Payments (B)\n\tWeekly(C)");
        System.out.print("\n\n\tEnter Selection (A, B, C): ");
        selection = (char)System.in.read();
        System.out.print("Your payment for a lot of "
                        + lotSize + " square feet is ");

        if (selection == 'A')
            System.out.print("\none payment of " + weeklyFee * 20);
        else if (selection == 'B')
            System.out.print("\ntwo payments of " + ((weeklyFee * 20) / 2 + 5) );
        else if (selection == 'C')
            System.out.print("\ntwenty weekly payments of " + (weeklyFee + 3));
        else
            System.out.print("\nnot available due to an invalid payment selection...");
    }
}

7a.
// Balance.java
// Chapter 4, Section A, Exercise 7a
public class Balance {
    public static void main (String[] args) throws Exception {
        double checkingBalance = 1500.50;
        double savingsBalance = 1500.70;
        if (checkingBalance > savingsBalance)
            System.out.println("Checking is higher");
        else
            System.out.println("Checking is not higher");
    }
}
7b.
// Balance2.java
// Chapter 4, Section A, Exercise 7b
public class Balance2 {
    public static void main (String[] args) throws Exception {
        double checkingBalance = 1500.50;
        double savingsBalance = 0;
        if ((checkingBalance < 0) && (savingsBalance < 0))
            System.out.println("Both accounts in the red");
        else if ((checkingBalance < savingsBalance)
                        && (checkingBalance >= 0))
        System.out.println("Both accounts are in the black");
    }
}
8.
// Employee.java
// Chapter 4, Section A, Exercise 8
public class Employee {
    private static  int COMPANY_ID = 12345;
    private int empNum;
    private double empSalary;
    
    Employee( ) throws Exception {
        System.out.print("Enter 3-digit employee number: ");
        // temp chars to accept bytes from input stream
        char a1, a2, a3;
        // temp numbers used in converting the chars
        int n1, n2, n3;
        // a dummy variable to throw away the Enter key
        int ta;
        a1 = (char)System.in.read(); // read first digit
        a2 = (char)System.in.read(); // read second digit
        a3 = (char)System.in.read(); // read third digit
        ta = System.in.read(); // get rid of newline char
        ta = System.in.read(); // get rid of newline char
        n1 = Character.digit(a1, 10); // convert to a number
        n2 = Character.digit(a2, 10); // convert to a number
        n3 = Character.digit(a3, 10); // convert to a number
        // put the number back together
        empNum = (n1*100) + (n2*10) + n3;
        System.out.println("empNum is " + empNum);
    }
    
    public void showCompanyID() {
        System.out.println("Worker " + empNum
                        + " has company ID " + COMPANY_ID);
    }
}
Chapter 4 - Section B
Questions
1. d 7. b 13. c
2. c 8. c 14. b
3. a 9. b 15. d
4. d 10. d 16. c
5. d 11. c 17. c
6. a 12. b 18. c
19. c

Exercises
1.
// PickEmployee.java
// Chapter 4, Section B, Exercise 1
public class PickEmployee {
    public static void main (String[] args) throws Exception {
        char selection;
        System.out.print("Enter an initial (A, B or Z): ");
        selection = (char)System.in.read();
        switch(selection) {
            case 'A':
                System.out.println("Armando");
                break;
            case 'B':
                System.out.println("Bruno");
                break;
            case 'Z':
                System.out.println("Zachary");
                break;
            default:
                System.out.println("No such employee");
        }
    }
}
2.
// GetVowel.java
// Chapter 4, Section B, Exercise 2
public class GetVowel {
    public static void main (String[] args) throws Exception {
        char selection;
        System.out.print("Enter a vowel: ");
        selection = (char)System.in.read();
        switch(selection) {
            case 'a': 
            case 'A':
                System.out.println(selection + " is a vowel");
                break;
            case 'e': 
            case 'E':
                System.out.println(selection + " is a vowel");
                break;
            case 'i': 
            case 'I':
                System.out.println(selection + " is a vowel");
                break;
            case 'o': 
            case 'O':
                System.out.println(selection + " is a vowel");
                break;
            case 'u': 
            case 'U':
                System.out.println(selection + " is a vowel");
                break;
            default:
                System.out.println(selection + " is NOT a vowel");
        }
    }
}
3.
// IQ.java
// Chapter 4, Section B, Exercise 3
public class IQ {
    public static void main (String[] args) throws Exception {
        int iqScore = 285;
        if (iqScore < 0 || iqScore > 200)
            System.out.println(iqScore + " is an invalid IQ score");
        else if (iqScore == 100)
            System.out.println(iqScore + " is average");
        else if (iqScore < 100)
            System.out.println(iqScore + " is below average");
        else
            System.out.println(iqScore + " is above average");
    }
}
4.
// Admissions2.java
// Chapter 4, Section B, Exercise 4
public class Admissions2 {
    public static void main (String[] args) throws Exception {
        double gpa = 3.5;
        int score = 59;
        System.out.println("The Grade Point Average is " + gpa);
        System.out.println("The Score is " + score);
        if (gpa >= 3.6 && score >= 60)
            System.out.println("Accept");
        else if (gpa >= 3.0 && score >= 70)
            System.out.println("Accept");
        else if (gpa >= 2.6 && score >= 80)
            System.out.println("Accept");
        else if (gpa >= 2.0 && score >= 90)
            System.out.println("Accept");
        else
            System.out.println("Reject");
    }
}
5.
// Payroll2.java
// Chapter 4, Section A, Exercise 5
public class Payroll2 {
    public static void main (String[] args) throws Exception {
        double hourlyRate = 25;
        double hoursWorked = 40;
        double withholdingTax;
        double pctTax = 0.0;
        double grossPay = hourlyRate * hoursWorked;
        if (grossPay <= 300.00)
            pctTax = .10;
        else if (grossPay >= 300.01 && grossPay <= 400.00)
            pctTax = .12;
        else if (grossPay >= 400.01 && grossPay <= 500.00)
            pctTax = .15;
        else if (grossPay >= 500.01)
            pctTax = .20;
        withholdingTax = grossPay * pctTax;
        System.out.println("The gross pay for "
                        + hoursWorked + " hours worked"
                        + " at a rate of " + hourlyRate + " per hour is "
                        + grossPay + "\nThe net pay is "
                        + (grossPay - withholdingTax)
                        + " based on tax rate of " + pctTax);
    }
}
6.
// PetAdvice.java
// Chapter 4, Section B, Exercise 6
public class PetAdvice {
    public static void main (String[] args) throws Exception {
        char abode, hours;
        System.out.print("Enter A (apartment), H (house), D (dormitory): ");
        abode = (char)System.in.read();
        System.in.read();
        System.in.read();
        System.out.println("How many hours do you spend at home per day? ");
        System.out.print("Enter A (18 or more), B (10 to 17), "
                + "D (6 to 7) or E (0 - 5): ");
        hours = (char)System.in.read();
        System.in.read();
        System.in.read();
        System.out.print("Your pet recommendation is ");
        if ((abode == 'H') && (hours == 'A'))
            System.out.println("Pot bellied pig");
        else if ((abode == 'H') && (hours == 'B'))
            System.out.println("Dog");
        else if ((abode == 'H') && (hours == 'D' || hours == 'E'))
            System.out.println("Snake");
        else if ((abode == 'A') && (hours == 'A' || hours == 'B'))
            System.out.println("Cat");
        else if ((abode == 'A') && (hours == 'D' || hours == 'E' || hours == 'C'))
            System.out.println("Hamster");
        else if ((abode == 'D') && (hours != 'E'))
            System.out.println("Fish");
        else if ((abode == 'D') && (hours == 'E'))
            System.out.println("Ant Farm");
        else
            System.out.println("not able to be determined");
    }
}
7.
// Siblings.java
// Chapter 4, Section B, Exercise 7
public class Siblings {
    public static void main (String[] args) {
        int myNumberOfSiblings = 3;
        int yourNumberOfSiblings = 5;
        if (myNumberOfSiblings > yourNumberOfSiblings)
            System.out.println("I have " + myNumberOfSiblings
                        + " siblings and you have " + yourNumberOfSiblings
                        + "\nI have more siblings ");
        else if (myNumberOfSiblings < yourNumberOfSiblings)
            System.out.println("I have " + myNumberOfSiblings
                        + " siblings and you have " + yourNumberOfSiblings
                        + "\nYou have more siblings ");
        else
            System.out.println("We have the same number of siblings: " +
                        myNumberOfSiblings );
    }
}
8.
// Credits.java
// Chapter 4, Section B, Exercise 8
public class Credits {
    public static void main (String[] args) {
        int myNumberOfCredits = 124;
        int yourNumberOfCredits = 50;
        if (myNumberOfCredits > yourNumberOfCredits)
            System.out.println("I have " + myNumberOfCredits
                                + " Credits and you have " + yourNumberOfCredits
                                + "\nI have more Credits ");
        else if (myNumberOfCredits < yourNumberOfCredits)
            System.out.println("I have " + myNumberOfCredits
                                + " Credits and you have " + yourNumberOfCredits
                                + "\nYou have more Credits ");
        else
            System.out.println("We have the same number of Credits: "
                                + myNumberOfCredits );
    }
}
9.
// Store.java
// Chapter 4, Section B, Exercise 9
public class Store {
    public static void main (String[] args) throws Exception {
        char sel1 = 'x', sel2 = 'x', yesNo = 'x';
        double cost = 0.0;
        System.out.println("\tMenu\n\n\tHammer, 5.99 (a)\n\tSaw, 11.99 (b)" 
                        + "\n\tShovel,  25.99 (c)");
        System.out.print("\n\n\tEnter Selection (a, b, c): ");
        sel1 = (char)System.in.read();
        System.in.read();
        System.in.read();
        System.out.print("\n\nSelect another product (y or n): ");
        yesNo = (char)System.in.read();
        System.in.read();
        System.in.read();
        if (yesNo == 'y') {
            System.out.println("\tMenu\n\n\tHammer, 5.99 (a)\n\tSaw, 11.99 (b)" +
                            "\n\tShovel, 25.99 (c)");
            System.out.print("\n\n\tEnter Selection (a, b, c): ");
            sel2 = (char)System.in.read();
            System.in.read();
            System.in.read();
        }
        switch(sel1) {
            case 'a':
                cost = 5.99;
                break;
            case 'b':
                cost = 11.99;
                break;
            case 'c':
                cost = 25.99;
        }
        switch(sel2) {
            case 'a':
                cost = cost + 5.99;
                break;
            case 'b':
                cost = cost + 11.99;
                break;
            case 'c':
                cost = cost + 25.99;
        }
        System.out.println("\nThe cost of your item is: " + cost);
    }
}
Chapter 4 - Section C
Questions
1. b 8. b 15. d
2. b 9. a 16. b
3. a 10. c 17. b
4. d 11. c 18. b
5. b 12. d 19. a
6. a 13. a 20. a
7. b 14. b

Exercises
1.
// EvenNums.java
// Chapter 4, Section C, Exercise 1
public class EvenNums {
    public static void main (String[] args) throws Exception {
        for (int i = 2; i <= 100; i++)
            if ((i % 2) == 0)
                System.out.println(i);
    }
}
2.
// ABCInput.java
// Chapter 4, Section C, Exercise 2
public class ABCInput {
    public static void main (String[] args) throws Exception {
        char selection = 'x';
        while (selection != 'Q') {
            System.out.print("Enter Selection (A, B, C, Q): ");
            selection = (char)System.in.read();
            System.in.read();
            System.in.read();
            switch(selection) {
                case 'Q':
                    break;
                case 'A': 
                case 'B': 
                case 'C':
                    System.out.println("Good Job!");
                    break;
                default:
                    System.out.println("Invalid selection");
            }
        }
    }
}
3.
// TableOfSquares.java
// Chapter 4, Section C, Exercise 3
public class TableOfSquares {
    public static void main (String[] args) {
        for (int i = 1; i <= 20; i++)
            System.out.println("Integer " + i +
                                " squared is " + i * i);
    }
}
4.
// Sum50.java
// Chapter 4, Section C, Exercise 4
public class Sum50 {
    public static void main (String[] args) throws Exception {
        int total = 0;
        for (int i = 1; i <= 50; i++)
            total += i;
        System.out.println("The total of the integers from 1 to 50 is " + total);
    }
}
5.
// EverySum.java
// Chapter 4, Section C, Exercise 5
public class EverySum {
    public static void main (String[] args) {
        int sum = 0;
        for (int i = 1; i <= 50; i++) {
            sum += i;
            System.out.print(" " + sum);
        }
    }
}
6.
// Perfect.java
// Chapter 4, Section C, Exercise 6
public class Perfect {
    public static void main (String[] args){
        for (int i = 2; i <= 1000; i++) {
            if (perfect(i) == true)
                System.out.println("The number " + i
                                    + " is perfect");
        }
    }
    public static boolean perfect(int n){
        int sum = 1;
        for (int j = 2; j <= n/2; j++)
            if (n % j == 0)
                sum += j;
        if (sum == n)
            return true;
        return false;
    }
}
7.
// Investment.java
// Chapter 4, Section C, Exercise 7
public class Investment {
    public static void main (String[] args) throws Exception {
        double investment;
        int term;
        char selection;
        System.out.println("Select Investment Amount");
        System.out.print("Enter a (200,000), b (100,000), c (50,000): ");
        selection = (char)System.in.read();
        System.in.read();
        System.in.read();
        switch(selection) {
            case 'a':
                investment = 200000.00;
                break;
            case 'b':
                investment = 100000.00;
                break;
            case 'c':
                investment = 50000.00;
                break;
            default:
                investment = 0.0;
        }
        System.out.println("Select Number of Years");
        System.out.print("Enter a (30), b (20), c (15): ");
        selection = (char)System.in.read();
        System.in.read();
        System.in.read();
        switch(selection) {
            case 'a':
                term = 30;
                break;
            case 'b':
                term = 20;
                break;
            case 'c':
                term = 15;
                break;
            default:
                term = 0;
        }
        if (term == 0 || investment == 0) {
            System.out.println("Not enough information");
            return;
        }
        System.out.println("Your Investment:");
        for (int i = 1; i <= term; i++) {
            System.out.println("Year " + i
                            + " amount at 12% is "
                            + (investment * (Math.pow((1 + .12),i))));
        }
    }
}
8.
// Quiz.java
// Chapter 4, Section C, Exercise 8
public class Quiz {
    public static void main (String[] args) throws Exception {
        String javaQuestion = new String("Is Java better than C++ (enter y or n):");
        String cQuestion = new String("Is C++ better than Java (enter y or n):");
        String question;
        char selection, answer;
        int numCorrect = 0;
        System.out.println("Select Quiz");
        System.out.print("Enter a (C++), b (Java), c (EXIT): ");
        selection = (char)System.in.read();
        System.in.read();
        System.in.read();
        switch(selection) {
            case 'a':
                question = cQuestion;
                answer = 'n';
                break;
            case 'b':
                question = javaQuestion;
                answer = 'y';
                break;
            default:
                return;
        }
        System.out.print(question);
        char response = (char)System.in.read();
        System.in.read();
        System.in.read();
        if (response == answer) {
            System.out.println("Correct!");
            numCorrect++;
        }
        else
            System.out.println("Incorrect!" +
                            "\nCorrect answer is " + answer);
        System.out.println("Number of correct answers: " + numCorrect);
    }
}
9.
// Survey.java
// Chapter 4, Section C, Exercise 9
public class Survey {
    public static void main (String[] args) throws Exception {
        String ques1 = new String("Is Java better than C++? ");
        String ques2 = new String("Is C++ better than Java? ");
        String ques3 = new String("Is C better than Java? ");
        String ques4 = new String("Is Pascal better than Java? ");
        String question;
        char selection, answer, response;
        char another = 'y';
        int i;
        while (another == 'y') {
            int numCorrect = 0;
            for (i = 1; i <= 4; i++) {
                if (i == 1) {
                    question = ques1;
                    answer = 'y';
                }
                else if (i == 2) {
                    question = ques2;
                    answer = 'n';
                }
                else if (i == 3) {
                    question = ques3;
                    answer = 'n';
                }
                else {
                    question = ques4;
                    answer = 'n';
                }
                System.out.println("Enter y or n for the following questions");
                System.out.print(question);
                response = (char)System.in.read();
                System.in.read();
                System.in.read();
                if (response == answer) {
                    System.out.println("Correct!");
                    numCorrect++;
                }
                else
                    System.out.println("Incorrect!" +
                            "\nCorrect answer is " + answer);
            }
            System.out.println("\nNumber of correct answers: " + numCorrect);
            System.out.print("\nEnter another set of responses (y or n):");
            another = (char)System.in.read();
            System.in.read();
            System.in.read();
        }
    }
}
10a.
public class FixDebugFour01
// Adds your bill for burger and fries {
    public static void main(String[] args) throws Exception {
        char usersChoice;
        double bill = 0.0;
        System.out.println("Do you want a burger?");
        System.out.println("Enter y or n.");
        usersChoice= (char)System.in.read();
        System.in.read();
        System.in.read();
        if(usersChoice == 'y')
            bill +=2.59;
        System.out.println("Fries with that?");
        usersChoice = (char)System.in.read();
        if (usersChoice == 'y')
            bill+=.89;
        System.out.println("Bill is " + bill);
    }
}
10b.
public class FixDebugFour02{
// prints odd numbers
// prints new line after every 10 
    public static void main(String[] args)    {
        int num, count = 0;
        for(num = 1; num <= 100; num+=2){
            System.out.print(" " + num);
            ++count;
            if(count == 10) {
                count = 0;
                System.out.println();
            }
        }
        System.out.println("End of odd numbers");
    }
}
10c.
public class FixDebugFour03{
// start with a penny
// double it every day
// how much do you have in a month?

    public static void main(String[] args) {
        double money = .01;
        int day=1;
        while(day < 30) {
            money = 2 * money;
            ++day;
            System.out.println("After day " + day +
                            " you have " + money);
        }
    }
}
10d.
public class FixDebugFour04 {
    public static void main(String[] args) {
        char letter;
        int a = 0;
        for(a = 65; a <= 122; a++) {
            letter = (char)a;
             System.out.print(" " + letter);
            if((a==85)||(a == 105))
                System.out.println();
        }
        System.out.println("\nEnd of program");
    }
}