Quiz Discussion

Which of these statements is correct?

• 1]

  true and false are numeric values 1 and 0

• 2]

  true and false are numeric values 0 and 1

• 3]

  true is any non zero value and false is 0

• 4]

  true and false are non numeric values

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

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 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 have highest precedence?

• 1]

  ()

• 2]

  ++

• 3]

  *

• 4]

  >>

What will be the output of the following Java code?

    class operators 
    {
        public static void main(String args[])
        {
            int var1 = 5; 
            int var2 = 6;
            int var3;
            var3 = ++ var2 * var1 / var2 + var2;
            System.out.print(var3);
        } 
    }

• 1]

  10

• 2]

  11

• 3]

  12

• 4]

  56

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

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 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