Quiz Discussion

Which of the following operators can operate on a boolean variable?

   1. &&
   2. ==
   3. ?:
   4. +=

• 1]

  3 & 2

• 2]

   1 & 4

• 3]

   1, 2 & 4

• 4]

  1, 2 & 3

What will be the output of the following Java program?

    class bitwise_operator 
    {
        public static void main(String args[])
        {
            int var1 = 42;
            int var2 = ~var1;
            System.out.print(var1 + " " + var2);     	
        } 
    }

• 1]

  42 42

• 2]

  43 43

• 3]

  42 -43

• 4]

  42 43

Can 8 byte long data type be automatically type cast to 4 byte float data type?

• 1]

  true

• 2]

  false

What will be the output of the following Java program?

    class Output 
    {
        public static void main(String args[]) 
        {    
             int a = 1;
             int b = 2;
             int c = 3;
             a |= 4;
             b >>= 1;
             c <<= 1;
             a ^= c;
             System.out.println(a + " " + b + " " + c);
        } 
    }

• 1]

  3 1 6

• 2]

  2 2 3

• 3]

  2 3 4

• 4]

  3 3 6

What is the order of precedence (highest to lowest) of following operators?

    1. &    
    2. ^
    3. ?:

• 1]

  1 -> 2 -> 3

• 2]

  2 -> 1 -> 3

• 3]

  3 -> 2 -> 1

• 4]

  2 -> 3 -> 1

Modulus operator, %, can be applied to which of these?

• 1]

  Integers

• 2]

  Floating – point numbers

• 3]

  Both Integers and floating – point numbers

• 4]

  None of the mentioned

Which right shift operator preserves the sign of the value?

• 1]

  <<

• 2]

  >>

• 3]

  <<=

• 4]

  >>=

What should be expression1 evaluate to in using ternary operator as in this line?

 expression1 ?  expression2  :  expression3

• 1]

  Integer

• 2]

  Floating – point numbers

• 3]

  Boolean

• 4]

  None of the mentioned

Which of these lines of Java code will give better performance?

   1. a | 4 + c >> b & 7; 
   2. (a | ((( 4 * c ) >> b ) & 7 ))

• 1]

  1 will give better performance as it has no parentheses

• 2]

  2 will give better performance as it has parentheses

• 3]

  Both 1 & 2 will give equal performance

• 4]

  Dependent on the computer system

Which of these statements are incorrect?

• 1]

  The left shift operator, <<, shifts all of the bits in a value to the left specified number of times

• 2]

  The right shift operator, >>, shifts all of the bits in a value to the right specified number of time

• 3]

  The left shift operator can be used as an alternative to multiplying by 2

• 4]

  The right shift operator automatically fills the higher order bits with 0