Show the output of the following programs. (Hint: Draw a table and list the variables in the columns to trace these programs.)

• a

public class Test {
    /** Main method */
    public static void main(String[] args) {
        for (int i = 1; i < 5; i++) {
            int j = 0;
            while (j < i) {
                System.out.print(j + " ");
                j++;
            }
        }
    }
}

• b

public class Test {
   /** Main method */
   public static void main(String[] args) {
       int i = 0;
       while (i < 5) {
           for (int j = i; j > 1; j——)
               System.out.print(j + " ");
           System.out.println("****");
           i++;
       }
   }
}

• c

public class Test {
    public static void main(String[] args) {
        int i = 5;
        while (i >= 1) {
            int num = 1;
            for (int j = 1; j <= i; j++) {
                System.out.print(num + "xxx");
                num *= 2;
            }
            System.out.println();
            i——;
        }
    }
}

• d

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);
   }
}

Write a program that lets the user enter the loan amount and loan period in number of years and displays the monthly and total payments for each interest rate starting from 5% to 8%, with an increment of 1/8.

What is wrong with the following programs?

• a

public class ShowErrors {
    public static void main(String[] args) {
        int i;
        int j = 5;

        if (j > 3)
            System.out.println(i + 4);
    }
}

• b

 public class ShowErrors {
     public static void main(String[] args) {
         for (int i = 0; i < 10; i++);
         System.out.println(i + 4);
     }
 }

How many times is the println statement executed? for (int i = 0; i < 10; i++) for (int j = 0; j < i; j++) System.out.println(i * j)

SubtractionQuizLoop.java, generates five random subtraction questions. Revise the program to generate ten random addition questions for two integers between 1 and 15. Display the correct count and test time.

What is wrong if guess is initialized to 0 in line 11 in Listing 5.3?

What is the keyword break for? What is the keyword continue for? Will the following programs terminate? If so, give the output.

int balance = 10;
while (true) {
    if (balance < 9)
       break;
    balance = balance - 9;
}
System.out.println("Balance is " + balance);

int balance = 10;
while (true) {
    if (balance < 9)
        continue;
    balance = balance - 9;
}
System.out.println("Balance is " + balance);

Count the number of iterations in the following loops.

• a

int count = 0;
while (count < n) {
   count++;
}

• b

for (int count = 0;
   count <= n; count++) {
}

• c

int count = 5;
while (count < n) {
   count++;
}

• d

int count = 5;
while (count < n) {
    count = count + 3;
}

Identify and fix the errors in the following code: 1 public class Test { 2 public void main(String[] args) { 3 for (int i = 0; i < 10; i++); 4 sum += i; 5 6 if (i < j); 7 System.out.println(i) 8 else 9 System.out.println(j); 10 11 while (j < 10); 12 { 13 j ++; 14 } 15 16 do { 17 j ++; 18 } while (j < 10) 19 } 20 }

(Display numbers in a pyramid pattern) Write a nested for loop that prints the following output:

                1
              1 2 1
            1 2 4 2 1
          1 2 4 8 4 2 1
       1 2 4 8 16 8 4 2 1
     1 2 4 8 16 32 16 8 4 2 1
  1 2 4 8 16 32 64 32 16 8 4 2 1
1 2 4 8 16 32 64 128 64 32 16 8 4 2 1

Use nested loops that display the following patterns in four separate programs:

Pattern A       Pattern B        Pattern C       Pattern D
1               1 2 3 4 5 6               1     1 2 3 4 5 6
1 2             1 2 3 4 5               2 1     1 2 3 4 5
1 2 3           1 2 3 4               3 2 1     1 2 3 4
1 2 3 4         1 2 3               4 3 2 1     1 2 3
1 2 3 4 5       1 2               5 4 3 2 1     1 2
1 2 3 4 5 6     1               6 5 4 3 2 1     1

Will the program work if n1 and n2 are replaced by n1 / 2 and n2 / 2 in line 17 in Listing 5.9?

Can you always convert a while loop into a for loop? Convert the following while loop into a for loop int i = 1; int sum = 0; while (sum < 10000) { sum = sum + i; i++; }