Homework Assignments for CSC 175

Spring 2007

 

 

 

Homework 1 (Due Date 1/19/07):

  1. (25 points) Covert the following decimal numbers to hexadecimal and binary numbers:
    1. 300
    2. 3033
    3. 100
    4. 84
    5. 38
    6. 23
    7. 48
    8. 10
    9. 66
    10. 128
  2. (25 points) Convert the following binary numbers to hexadecimal and decimal numbers:
    1. 10011010b
    2. 11001010b
    3. 10000000b
    4. 11101110b
    5. 00110011b
    6. 11100011b
    7. 00001000b
    8. 00111111b
    9. 00011111b
    10. 11111100b
  3. (25 points) Convert the following hexadecimal numbers to binary and decimal numbers:
    1. AFEFh
    2. 93h
    3. 100h
    4. 85h
    5. CBAh
    6. BACh
    7. DABh
    8. EEh
    9. 4321h
    10. 52h
  4. (25 points) List and define the five major hardware components of a computer.
  5. (100 points) Textbook pages 26, Program Exercise #1.1, sections 1, 2, 3, 4, 5, 6, 7, 8.

 

Homework 2 (Due Date 1/29/07):

1. (25 points) Categorize the following as Java keyword, valid identifier, or invalid identifier:

    1. abstract
    2. INT
    3. -new
    4. YesNo
    5. goto
    6. Home+
    7. Float
    8. First_1
    9. try
    10. 521Now

2. (25 points) Given the following declarations:

int A = 1;

int A1;

double D = 1.0;

double D1;

int B = 1;

int C = 1;

What are the results of the following Java expressions?

a.       A1 = 32/10;

b.      A1 = 25 % 6 + 3 * 3 – 1;

c.       A1 = 25 % (6 + 3) * 3 – 1;

d.      A1 %= 7/A + 6;

e.       A1 = 5.0 / D;

f.        D1 = 6.0 / D;

g.       D1 = 44/10;

h.       D1 -= 6.3 * 3 + B++;

i.         D1 += 6.3 * 3 + (++C);

j.        D1 = 10 % 20;

3. (25 points) Evaluate the following:

a.       int i = ‘1’;

b.      int j = ‘1’ + ‘2’;

c.       int k = ‘a’;

d.      char c = 90;

e.       char c = 10 + 50;

f.        int l = ‘1’ + 2;

g.       char c = “b”;

h.       int m = 1 + ‘2’ + 3;

i.         char d = 200;

j.        int n = ‘9’ + ‘8’;

4. (25 points) Show the output of the following program:

public class Test {

            public static void main (String[] args) {

                        char x = ‘A’;

                        char y = ‘C’’

                        System.out.println(++y) ;

                        System.out.println(y++);

                        System.out.println(y) ;

                        System.out.println(x > y);

                        System.out.println(x – y);

            }

}

5. (100 points) Programming Problem: Textbook page 63, problem 2.4 and page 64, problem 2.6.

 

Homework 3 (Due Date 2/14/07):

1. (25 points) For the following code segment:

if (x > 2) {

      if (y > 2) {

                  int z = x + y;

                  System.out.println(“z is “ + z);

      }

}

else {

      System.out.println(“x is “ + x);

}

a.       What is output if x = 2 and y = 1?

b.      What is output if x = 3 and y = 2?

c.       What is output if x = 0 and y = 3?

d.      What is output if x = 2 and y = 2?

e.       What is output if x = 2 and y = 5?

  1. (25 points) Use the switch statement to rewrite the following if statement.

if (a == 1)

      x += 1;

else if (a == 2)

      x += 5;

else if (a == 4)

      x += 10;

else if (a == 5)

      x += 15;

 

3.  (25 points) Assume x and y are int type.  Which are correct Java expressions?

a. x > y > 0

b. x = y && y

c. x /= y

d. x or y

e. x and y

f. (x != 0) || (x = 0)

g. (x & y) | (x == y)

h. (x != y) && (y == x)

i. (y = x) && (x = y)

j. (x || true)

 

4.  (25 points) Assume that x is 1, show the results of the following Boolean expressions:

a. (true) && (3 > 4)

b. !(x > 0) && (x > 0)

c. (x > 0) || (x < 0)

d. (x != 0) || (x == 0)

e. (x >= 0) || (x < 0)

f. (x != 1) == !(x == 1)

g. (x == 1) == true

h. (x < 1) && false || (x > 1)

i. (x >= 1) == false || true

j. (x <= 0) && (x != 5) || false

 

5. (100 points) Programming Problems: Textbook page 94, problems 3.9 and 3.12.

 

Homework 4 (Due Date 2/26/07):

 

  1.  (25 points) What is displayed by the following code?

                  int i = 1;

                  while(i < 15) {

                        if ((i++) % 2 != 0) {

                              System.out.println(i);

                        }

                  }

 

  1. (25 points) Show the output for the following program.

public class Test {

        public static void main(String [] args) {

                    int i = 0;

                    while (i < 5) {

                                for(int j = 1; i > 1; j--) {

                                            System.out.print(j + “ “);

                                }

                                System.out.println(“*****”);

                    }

        }

}

3.  (25 points) Show the output of the following program.

public class Test {

        public static void main (String[] args) {

                    for (int i = 1; i < 5; i++) {

                                int j = 0;

                                while (j < i) {

                                            System.out.println(j + " ");

                                            j++;

                                }

                    }

        }

} 

4.  (25 points) Show the output of the following program:

public class Test {

        public static void main (String[] args) {

                    int i = 1;

                    do {

                                int num = 1;

                                for (int j = 1; j <= i; j++) {

                                            System.out.print(num + "G");

                                            num += 2;

                                }

                                System.out.println();

                                i++;

                    }

                    while (i <= 5);

        }

}

 

5.  (100 points) Programming Problem: Textbook page 124, problem 4.24

 

Homework 5 (Due Date 3/21/07):

  1. (25 points) For each of the following, decide whether a void method or nonvoid method is the most appropriate implementation.

a.       Printing a calendar for a month.

b.      Computing a square root.

c.       Testing whether a number is even, and returning true if it is.

d.      Printing a message a specified number of times.

e.       Finding the corresponding upper case letter given a lowercase letter.

  1. (25 points) What is meant by passed by value?  Show the results of the following program.

public class HW5P2 {

      public static void main (String [] args) {

                  int i = 0;

                  while (i <= 4) {

                              xMethod(i);

                              i++;

                  }

                  System.out.println("i is " + i);

      }

      public static void xMethod (int i) {

                  do {

                              if (i % 3 != 0)

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

                              i--;

                  }

                  while (i >= 1);

                  System.out.println();

      }

}

 

  1. (25 points) Evaluate the following method calls:

a.       Math.sqrt(25)

b.      Math.pow(8 3)

c.       Math.max(2, Math.min(3,4))

d.      Math.round(math.abs(-2.5)

e.       Math.ceil(2.5)

  1. (25 points) Show the output of the following program.

public class Test {

            public static void main(String [] args) {

                        xMethod(5);

            }

            public static void xMethod (int n) {

                        if(n > 0) {

                                    System.out.print(n + “ “);

                                    xMethod(n – 1);

                        }

            }

}

  1. (100 points) Programming Problem:

a.       Textbook page 164, problem 5.9

b.      Textbook page 166, problem 5.17


Homework 6 (Due Date 3/30/07):

  1. (25 points) What is the printout of the following code?

int x = 100;

int [] numbers = new int [x];

x = 200;

System.out.println(“x is “ + x);

System.out.println(“The size of numbers is “ + numbers.lenght);

  1. (25 points) Which of the following statements are valid array declarations?

a.       int i = new int(30);

b.      double d[] = new double(30);

c.       char[] r = new char(1..30);

d.      int[i] = (3, 4, 3, 2);

e.       float f[] = {2.3, 4.5, 5.6};

  1. (25 points) Show the contents of the array after the allocations of each line:

int[] array = new int[5][6];

int[] x = {1, 2};

array[0] = x;

System.out.println(“array[0][1] is “ + array[0][1]);

 

  1.  (25 points) Declare and create a 4 X 5 int matrix.
  2. (100 points) Programming Problem: Textbook page 205, problem 6.8

 

Homework 7 (Due Date 4/18/07):

1.      (25 points) What is the printout of the following code?

public class Foo {

            private boolean x;

            public static void main (String [] args) {

                        Foo foo = new Foo();

                        System.out.println(foo.x);

            }

}

2.      (25 points) Show the output of the following program.

public class Test {

            public static void main(String [] args) {

                        Count myCount = new Count();

                        int times = 0;

                        for (int i = 0; i < 100; i++) {

                                    increment(myCount, times);

                        }

                        System.out.println(“count is “ + myCount.count);

                        System.out.println(“times is “ + times);

            }

            public static void increment (Count c, int times) {

                        c.count++;

                        times++;

            }

}

 

Class Count {

            public int count;

            Count(int c) {

                        count = c;

            }

            Count() {

                        count = 1;

            }

}

3.      (25 points) Show the output for the following program.

public static Test {

            public static void main(String [] args) {

                        T t = new T();

                        swap (t);

                        System.out.println(“e1 = “ + t.e1) + “ and e2 = “ + t.e2);

            }

            public static void swap(T t) {

                        int temp = t.e1 ;

                        t.e1 = t.e2 ;

                        t.e2 = temp ;

            }

}

class T {

            int e1 = 1 ;

            int e2 = 2 ;

}

4.      (25 points) What is the output of the following program?

public class Foo {

            static int i = 0;

            static int j = 0;

            public static void main(String [] args) {

                        int i = 2;

                        int k = 3;

                        {

                                    int j = 3;

                                    System.out.println(“i + j is : + (i + j));

                        }

                        k = i + j;

                        System.out.println(”k is ” + k);

                        System.out.println(“j is “ + j);

}

}

5.      (100 points) Programming Problem: Textbook page 257, problem 7.4

 

Homework 8 (Due Date 4/27/07):

1.      (25 points) Suppose that s1, s2, s3, and s4 are four strings, given as follows:

String s1 = “Welcome to Java”;

String s2 = s1;

String s3 = new String (“Welcome to Java”);

String s4 = s3.intern();

What is the result of the following expressions?

a.       s1 == s2

b.      s2 == s3

c.       s1.equals(s2)

d.      s2.equals(s3)

e.       s1.charAt(3)

f.        s1.indexOf(‘j’)

g.       s1.lastIndesOf(“o”, 15)

h.       s1.length()

i.         s1.substring(5, 11)

j.        s1.replaceAll(“o”, “T”)

2.      (25 points) Suppose that s1 and s2 are given as follows:

StringBuffer s1 = new StringBuffer(“Java”);

StringBuffer s2 = new StringBuffer(“HTML”);

Show the results of the following expressions of s1 after each statement.  Assume that the expressions are independent.

a.       s1.append(“ is fun”);

b.      s1.append(s2);

c.       s1.insert(2, “is fun”);

d.      s1.insert(1, s2);

e.       s1.charAt(2);

f.        s1.lenght();

g.       s1.deleteCharAt(3);

h.       s1.reverse();

i.         s1.replace(1, 2, “Computer”);

j.        s1.substring(1, 3);

3.      (25 points) Given the following program:

1    import java.util.StringTokenizer

2   

3    public class TestStringTokenizer {

4                public static void main(String [] args) {

5                            String s = “Java is cool.”;

6                            StringTokenizer tokenizer = new StringTokenizer(s, “v.”);

7   

8                            System.out.println(“The total number of tokens is “ + tokenizer.countTokens());

9   

10

11                                                    while (tokenizer.hasMoreTokens()) {

12                                      System.out.println(tokentizer.nextToken());

13                          }

14                          System.out.println(“Any tokens left? “ + tokenizer.countTokens());

15              }

16  }

a.       What is the output?

b.      What would be the output if Line 6 is replaced by the following code?

StringTokenizer tokenizer = new StringTokenizer(s, “v.”, true);

4.      (25 points) Suppose that s1 and s2 are two stings.  Which of the following statements or expressions are incorrect?

a.       String s = new String(“new string”);

b.      String s3 = s1 + s2;

c.       Strings3 = s1 – s2;

d.      s1 == s2;

e.       s1 >= s2;

f.        s1.compareTo(s2);

g.       int i = s1.length();

h.       char c = s1(0);

i.         char c = s1.charAt(s1.lenght());

j.        int i = s1.lenght() - s2.length();

5.      (100 points) Programming Problem: Textbook page 297, problem 8.3