Quiz Discussion

Which of these statements are incorrect?

• 1]

  Assignment operators are more efficiently implemented by Java run-time system than their equivalent long forms

• 2]

  Assignment operators run faster than their equivalent long forms

• 3]

  Assignment operators can be used only with numeric and character data type

• 4]

  None of the mentioned

Which of these is returned by “greater than”, “less than” and “equal to” operators?

• 1]

  Integers

• 2]

  Floating – point numbers

• 3]

  Boolean

• 4]

  None of the mentioned

What will be the output of the following Java program?

class Output 
{
        public static void main(String args[]) 
        {    
             int a,b,c,d;
             a=b=c=d=20
            a+=b-=c*=d/=20
           System.out.println(a+" "+b+" "+c+" "+d);
 
        } 
}

• 1]

  compile time error

• 2]

  runtime error

• 3]

  a=20 b=0 c=20 d=1

• 4]

  none of the mentioned

What will be the output of the following Java program?

    class leftshift_operator 
    {
        public static void main(String args[]) 
        {        
             byte x = 64;
             int i;
             byte y; 
             i = x << 2;
             y = (byte) (x << 2)
             System.out.print(i + " " + y);
        } 
    }

• 1]

  0 64

• 2]

  64 0

• 3]

  0 256

• 4]

  256 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 is the value stored in x in the following lines of Java code?

   int x, y, z;
    x = 0;
    y = 1;
    x = y = z = 8;

• 1]

  0

• 2]

  1

• 3]

  9

• 4]

  8

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 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 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 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