CS101 Algorithms and Programming I - Section: 03 - Quizzes

Quiz 1 (10 Feb 2016)

• The class should have a constructor, which takes “car speed” as an argument.
• The class should have methods to go forwards and backwards, which take the “movement duration” as an argument.
• The class should also have a method to get the current position.
• Assume that
  • the “car speed” is in "meters per second”
  • the “movement duration” argument is in "seconds”
  • initial position of the car is 0
• You may use double or int for the speed and movement duration arguments.
• You are not required to write comments.

/**
   A toy car model.
 */
public class ToyCar { 
    /** 
       The speed of the car, in meters/second.
     */
    private double speed;

    /** 
       One-dimensional position of the car, in meters.
     */
    private double position;

    /** 
       Constructs a new car instance, with a spefied movement speed.
       @param carSpeed  The speed of the car, int meters/second.
     */
    public ToyCar(double carSpeed) {
        speed = carSpeed;
        position = 0;
    }

    /** 
       Move car forwards for a fixed duration of time.
       @param duration Movement duration in seconds.
     */
    public void goForwards(double duration) {
        position = position + duration * speed;
    }

    /** 
       Move car backwards for a fixed duration of time.
       @param duration Movement duration in seconds.
     */
    public void goBakwards(double duration) {
        position = position - duration * speed;
    }

    /** 
       Get the current position of the car, relative to the starting point.
       @return Current car position, in meters. 
     */
    public double getPosition() {
        return position;
    }
}

    

Quiz 2 (19 Feb 2016)

• The class should have a constructor, which takes “the value of USD in TRY” (the conversion rate) as an argument.
• The class should have two methods:
  • to convert USD to TRY
  • to convert TRY to USD
• Write another class that uses Converter. In the main method, do the following:
  • declare a constant for USD-to-TRY conversion rate (eg, 3),
  • convert 5 USD to TRY, and print,
  • convert 18 TRY to USD, and print.
• You are not required to write comments.

/**
  A utility class for conversion between the USD and TRY currencies.
 */
public class Converter {

    /** 
      The conversion rate.
     */
    private double rate;

    /** 
      Constructs a converter class with a given conversion rate.
      @param rate The conversion rate, ie. the value of 1 USD in TRY.
     */
    public Converter(double rate) {
        this.rate = rate;
    }

    /**
      Convert USD to TRY.
      @param amount The amount in USD to be converted.
     */
    public double convertUsdToTry(double amount) {
        return amount * rate;
    }

    /**
      Convert TRY to USD.
      @param amount The amount in TRY to be converted.
     */
    public double convertTryToUsd(double amount) {
        return amount / rate;
    }

}


/**
  A usage example for the Converter class.
 */
public class ConverterTester {
    public static void main(String [] args) {
        final double USD_TRY_RATE = 3; // any constant value is OK for grading
        Converter defaultConverter = new Converter(USD_TRY_RATE);
        System.out.print("5 USD in TRY: "); // not required in the question
        System.out.println(defaultConverter.convertUsdToTry(5));
        System.out.print("18 TRY in USD: "); // not required in the question
        System.out.println(defaultConverter.convertTryToUsd(18));
    }
}

    

Quiz 3 (11 Mar 2016)

• age is less than 3 months: “baby”
• age is 3 months or above, but less than 18 years: “child”
• age is 18 years and above: “adult”

import java.util.Scanner;

public class Q3 {
    public static void main( String [] args ) {
        Scanner in = new Scanner( System.in );
        int count = 0;
        while ( count < 10 ) {
            count++;
            System.out.print("Enter age: ");
            double age = in.nextDouble();
            if ( age >= 18 ) {
                System.out.println("adult");
            } else if ( age >= 0.25 ) {
                System.out.println("child");
            } else 
                System.out.println("baby");
            }
        }
    }
}

    

Quiz 4 (23 Mar 2016)

• read numbers (as floating point numbers)
• print their average
• start from beginning, and prompt the user again

import java.util.Scanner;

public class Q4 {
    public static void main (String[] args) {
        Scanner in = new Scanner( System.in );
        int count = 1;
        while( count > 0 ) {
            System.out.print("The number of values to be read: "); 
            count = in.nextInt();
            double sum = 0;
            for (int j = 0; j < count; ++j) {
                System.out.print("Enter value: "); 
                sum = sum + in.nextDouble();
            }
            if ( count > 0 ) { 
                System.out.printf("Average: %.1f\n",sum/count); 
            }
        }
    } 
} 
    

Quiz 5 (30 Mar 2016)

    public static double squaredVectorNorm(double [] vec) {
        double res = 0;
        for ( int j = 0; j < vec.length; ++j ) {
            res += vec[j] * vec[j];
        }
        return res;
    }
    

Quiz 6 (13 Apr 2016)

    /**
     * Compute the sum of diagonal elements in a given matrix.
     *
     *  @param mat Matrix, represented as a 2D array.
     *
     *  @return The sum of diagonal elements.
     */
    public static double trace(double [][] mat) {
        double sum = 0;
        int nDiag = mat.length; // nrows
        if (mat.length > 0 && nDiag > mat[0].length) { // handle empty matrix
            nDiag = mat[0].length; // ncols
        }
        for ( int i = 0; i < nDiag; ++i ) {
            sum += mat[i][i];
        }
        return sum;
    }
    

Quiz 7 (22 Apr 2016)

        BankAccount a1 = new BankAccount(100);
        BankAccount a2 = new BankAccount(500);
        BankAccount a3 = a1;
        a1.setAccountNumber(300);
        BankAccount a4 = new BankAccount(1000);
        System.out.println(a1);
        System.out.println(a2);
        System.out.println(a3);
        System.out.println(a4);
        

        Account: 300 balance: 100.0
        Account: 1002 balance: 500.0
        Account: 300 balance: 100.0
        Account: 1003 balance: 1000.0
    

Quiz 8 (27 Apr 2016)

        AccountManager mng = new AccountManager();

        Account a1 = new Account("Joe");
        Account a2 = new Account("Marvin");
        Account a3 = a1;
        Account a4 = a3;

        mng.addAccount(a1);
        mng.addAccount(a2);
        mng.addAccount(a3);
        mng.addAccount(a4);

        mng.depositAll(10);
        a4.deposit(60);
        a3.deposit(100);
        a1.withdraw(10);
        mng.printAll();