Quiz Discussion

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

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

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 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

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

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

• 1]

  1

• 2]

  2

• 3]

  3

• 4]

  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 statements are incorrect?

• 1]

  Equal to operator has least precedence

• 2]

  Brackets () have highest precedence

• 3]

  Division operator, /, has higher precedence than multiplication operato

• 4]

  Addition operator, +, and subtraction operator have equal precedence

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