Spring Semester 2004

The practical exam is coming, let's work out some problems.

Problem 1 Write a program stenographer that

• accepts lines of text from the user and
• translates them (one by one) in shorthand.

For the purposes of this exercise

• let's define shorthand notation as the one in which
• all vowels are removed from all the words everywhere.

Good evening, and welcome to Minneapolis!

Gd vnng, nd wlcm t Mnnpls!

Solution

Write a program stenographer

class Stenographer {
    public static void main(String[] args) {

    } 
}

class Stenographer {
    public static void main(String[] args) {
        ConsoleReader c = new ConsoleReader(System.in); 
        System.out.print("Please type a line of text: "); 
        String line = c.readLine(); 

    } 
}

class Stenographer {
    public static void main(String[] args) {
        ConsoleReader c = new ConsoleReader(System.in); 
        System.out.print("Please type a line of text: "); 
        String line = c.readLine(); 
        for (int i = 0; i < line.length(); i++) {
            String temp = line.substring(i, i+1); 
            System.out.print(temp); 
        }
        System.out.println(); 
    } 
} 

class Stenographer {
    public static void main(String[] args) {
        ConsoleReader c = new ConsoleReader(System.in); 
        System.out.print("Please type a line of text: "); 
        String line = c.readLine(); 
        for (int i = 0; i < line.length(); i++) {
            String temp = line.substring(i, i+1); 
            if (temp.equalsIgnoreCase("A") ||
                temp.equalsIgnoreCase("E") ||
                temp.equalsIgnoreCase("I") ||
                temp.equalsIgnoreCase("O") ||
                temp.equalsIgnoreCase("U")) {
                // skip that letter 
            } else {
                System.out.print(temp); 
            }
        }
        System.out.println(); 
    } 
} 

school.cs.indiana.edu%java Stenographer
Please type a line of text: Good evening, and welcome to Minneapolis!
Gd vnng, nd wlcm t Mnnpls!
school.cs.indiana.edu%java Stenographer
Please type a line of text: The Stenographer program works pretty well!
Th Stngrphr prgrm wrks prtty wll!
school.cs.indiana.edu%

Problem 2 Take a look at this problem, and become clear how it works, first.

Your lab assignment seven (below) is based on this and the previous question.

Your task is to write a program that simulates a vending machine that sells items which are worth 65 cents.

Your program (called Vending) starts by greeting the user, then accepting coins.

The machine accepts one coin at a time and understands the following coins:

• nickel
• dime and
• quarter

When the amount exceeds 65 cents the program will print the change (if any) and thanks the user for making use of it. See below.

Example run:

prompt> java Vending
Welcome. Please enter coins:
coin> nickel
60 cents remaining
coin> quarter
35 cents remaining
coin> quarter
10 cents remaining
coin> quarter
Thank you. Your change is: 15 cents. 
Thanks for using this program. 

Here's a possible solution:

class Vending {
    public static void main(String[] args) {
        ConsoleReader console = new ConsoleReader(System.in); 
        System.out.println("Welcome. Please enter coins:"); 
        int amount = 0; 
        final int PRICE = 65; 
        while (amount < PRICE) {
            String coin; 
            System.out.print("coin> "); 
            coin = console.readLine(); 
            if (coin.equals("nickel")) {
                amount += 5; 
            } else if (coin.equals("dime")) {
                amount += 10; 
            } else if (coin.equals("quarter")) {
                amount += 25; 
            }
            if (amount < 65) {
                System.out.println((PRICE - amount) + " cents remaining."); 
            } else {
                System.out.println("Thank you. Your change is: " + 
                                   (amount - PRICE) + " cents."); 
            }
        }
        System.out.println("Thanks for using this program."); 
    }
} 

A201/A597 LAB ASSIGNMENT SEVEN

• cent
• nickel
• dime
• quarter and
• dollar

Example run:

prompt> java Vendor
Welcome. We sell stamps ($3.40) Please enter money:
enter> nickel nickel dollar dollar quarter
Thanks. Your credit is $2.35 I need $1.05 more.  
enter> cent cent
Thanks. Your credit is $2.37 I need $1.03 more. 
enter> dollar quarter
Thanks. Your credit is $3.62 The stamps are yours.
Your change is: $0.22
Thanks for using this program. 

Hints and Advice.

Your strategy should be simple:

• Keep reading lines until you have received enough money.
• Initially you start from having received nothing (zero).
• With each line you need to use a StringTokenizer.
• That's because more than one coin might be specified per line.
• So you need a loop for each line, to look at the words.
• Every word looked at translates into a coin value.
• After every line you check to see if you have enough money.
• If not, you keep going, asking for more (and indicating how much).
• So the loop for each line is inside a bigger loop for the conversation.
• But you knew that, already!