Quiz Discussion

 On applying Left shift operator, <<, on integer bits are lost one they are shifted past which position bit?

• 1]

  1

• 2]

  32

• 3]

  33

• 4]

  31

Decrement operator, −−, decreases the value of variable by what number?

• 1]

  1

• 2]

  2

• 3]

  3

• 4]

  4

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

What will be the output of the following Java code?

    class bool_operator 
    {
        public static void main(String args[]) 
        {    
             boolean a = true;
             boolean b = !true;
             boolean c = a | b;
 	     boolean d = a & b;
             boolean e = d ? b : c;
             System.out.println(d + " " + e);
        } 
    }

• 1]

  false false

• 2]

  true ture

• 3]

  true false

• 4]

  false true

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

What will be the output of the following Java program?

    class bitwise_operator 
    {
        public static void main(String args[]) 
        {    
             int a = 3;
             int b = 6;
 	         int c = a | b;
             int d = a & b;             
             System.out.println(c + " "  + d);
        } 
    }

• 1]

  7 2

• 2]

  7 7

• 3]

  7 5

• 4]

  5 2

What will be the output of the following Java program?

    class rightshift_operator 
    {
        public static void main(String args[]) 
        {    
             int x; 
             x = 10;
             x = x >> 1;
             System.out.println(x);
        } 
    }

• 1]

  10

• 2]

  5

• 3]

  2

• 4]

  20

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

What will be the output of the following Java code?

    class Output 
    {
        public static void main(String args[]) 
        {    
             int x , y = 1;
             x = 10;
             if (x != 10 && x / 0 == 0)
                 System.out.println(y);
             else
                 System.out.println(++y);
        } 
    }

• 1]

  1

• 2]

  2

• 3]

  Runtime error owing to division by zero in if condition

• 4]

  Unpredictable behavior of program

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