Quiz Discussion

With x = 0, which of the following are legal lines of Java code for changing the value of x to 1?

   1. x++;
   2. x = x + 1;
   3. x += 1;
   4. x =+ 1;

• 1]

  1, 2 & 3

• 2]

  1 & 4

• 3]

  1, 2, 3 & 4

• 4]

  3 & 2

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

 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

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 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 have highest precedence?

• 1]

  ()

• 2]

  ++

• 3]

  *

• 4]

  >>

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;
             int d;
             c = ++b;
             d = a++;
             c++;
             b++;
             ++a;
             System.out.println(a + " " + b + " " + c);
        } 
    }

• 1]

  3 2 4

• 2]

  3 2 3

• 3]

  2 3 4

• 4]

  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 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

Which of these is not a bitwise operator?

• 1]

  &

• 2]

  &=

• 3]

  |=

• 4]

  <=