2.3.1 - Introduction to Operators.

1. Which of the following is an example of a unary operator in C?

A) `+`
B) `x++`
C) `x + y`
D) `x - y`

Correct Answer: B) x++

2. What is the result of the expression `int x = ++y;` when `y` is initially 5?

A) `x = 5, y = 5`
B) `x = 6, y = 5`
C) `x = 5, y = 6`
D) `x = 6, y = 6`

Correct Answer: D) x = 6, y = 6

3. In a pre-increment operation (`++x`), when does the value of `x` increase by 1?

A) After it is used in an expression
B) Before it is used in an expression
C) Only if `x` is even
D) Only if `x` is odd

Correct Answer: B) Before it is used in an expression

4. What is the output of the following program?

                #include <stdio.h>
                int main() {
                    int x = 10, y = 20;
                    int p = ++x + ++y;
                    printf("%d\n", x);
                    printf("%d\n", y);
                    printf("%d\n", p);
                    return 0;
                }

A) 10 20 30
B) 11 21 32
C) 10 20 32
D) 11 21 30

Correct Answer: B) 11 21 32

5. What does the pre-decrement operator (`--x`) do in C?

A) Decreases the value of `x` after it is used in the expression
B) Increases the value of `x` after it is used in the expression
C) Decreases the value of `x` before it is used in the expression
D) Increases the value of `x` before it is used in the expression

Correct Answer: C) Decreases the value of x before it is used in the expression

6. In post-increment (`x++`), when is the value of the variable incremented?

A) After it is used in the expression
B) Before it is used in the expression
C) It does not increment the value
D) Immediately when the program runs

Correct Answer: A) After it is used in the expression

7. What will be the value of `p` in the following program?

                #include <stdio.h>
                int main() {
                    int x = 10, y = 20;
                    int p = x++ + y++;
                    printf("%d\n", p);
                    return 0;
                }

A) 30
B) 31
C) 32
D) 33

Correct Answer: A) 30

8. Which of the following statements correctly describes a post-decrement operation (`x--`)?

A) Decreases `x` before it is used in the expression
B) Increases `x` after it is used in the expression
C) Decreases `x` after it is used in the expression
D) Increases `x` before it is used in the expression

Correct Answer: C) Decreases x after it is used in the expression

9. What is the output of the following program?

                #include <stdio.h>
                int main() {
                    int a = 10, b = 100;
                    float c = 10.5, d = 100.5;
                    printf("++a = %d \n", ++a);
                    printf("--b = %d \n", --b);
                    printf("++c = %f \n", ++c);
                    printf("--d = %f \n", --d);
                    return 0;
                }

A) ++a = 10, --b = 100, ++c = 10.5, --d = 100.5
B) ++a = 11, --b = 99, ++c = 11.5, --d = 99.5
C) ++a = 11, --b = 99, ++c = 10.5, --d = 100.5
D) ++a = 10, --b = 99, ++c = 11.5, --d = 99.5

Correct Answer: B) ++a = 11, --b = 99, ++c = 11.5, --d = 99.5

10. What is the main difference between unary and binary operators in C?

A) Unary operators work on two operands, while binary operators work on one
B) Unary operators work on one operand, while binary operators work on two
C) Unary operators are faster than binary operators
D) Unary operators work only with integers

Correct Answer: B) Unary operators work on one operand, while binary operators work on two

2.3.1 - Introduction to Operators.

1. What is an operator in C?

A) A symbol that stores a value
B) A symbol that manipulates a value or variable
C) A function that calculates a value
D) A keyword that declares a variable

Correct Answer: B) A symbol that manipulates a value or variable

2. Which of the following is a unary operator?

A) +
B) ++
C) *
D) ==

Correct Answer: B) ++

3. In a pre-increment operation, which of the following is correct?

A) The variable is used first, then incremented
B) The variable is incremented first, then used
C) The variable is incremented, but not used in the expression
D) The variable is used, but not incremented

Correct Answer: B) The variable is incremented first, then used

4. What will be the output of the following code?

int x = 10, y = 20;
            int p = ++x + ++y;
            printf("%d\n", p);

A) 30
B) 31
C) 32
D) 33

Correct Answer: C) 32

5. In a pre-decrement operation, what happens to the variable?

A) The variable is incremented by 1
B) The variable is used first, then decremented by 1
C) The variable is decremented first, then used
D) The variable remains unchanged

Correct Answer: C) The variable is decremented first, then used

6. What will be the output of the following code?

int x = 10, y = 20;
            int p = --x - --y;
            printf("%d\n", p);

A) 10
B) -9
C) -10
D) -11

Correct Answer: C) -10

7. In a post-increment operation, which of the following is correct?

A) The variable is used first, then incremented
B) The variable is incremented first, then used
C) The variable is decremented, then used
D) The variable is decremented, but not used

Correct Answer: A) The variable is used first, then incremented

8. What will be the output of the following code?

int x = 10, y = 20;
            int p = x++ + y++;
            printf("%d\n", p);

A) 30
B) 31
C) 32
D) 33

Correct Answer: A) 30

9. In a postfix decrement operation, when is the variable decremented?

A) Before its value is used in the statement
B) After its value is used in the statement
C) It is not decremented
D) During the execution of the statement

Correct Answer: B) After its value is used in the statement

10. What will be the output of the following code?

int x = 10, y = 20;
            int p = x-- - y--;
            printf("%d\n", p);

A) 10
B) -9
C) -10
D) -11

Correct Answer: C) -10

11. Which of the following operators is used for binary operations?

A) ++
B) ==
C) +
D) --

Correct Answer: C) +

12. What will be the output of the following code?

int a = 10, b = 100;
            float c = 10.5, d = 100.5;
            printf("++a = %d \n", ++a);
            printf("--b = %d \n", --b);
            printf("++c = %f \n", ++c);
            printf("--d = %f \n", --d);

A) 11, 99, 11.5, 99.5
B) 10, 100, 10.5, 100.5
C) 11, 101, 11.5, 101.5
D) 10, 100, 10.5, 100.5

Correct Answer: A) 11, 99, 11.5, 99.5

2.3.2 - Arithmatic, Relatiional, Logical, Assignment and Operators.

13. Which operator is used for addition in C programming?

A) *
B) +
C) -
D) /

Correct Answer: B) +

14. What will be the result of the operation 9 % 4 in C programming?

A) 2
B) 3
C) 1
D) 0

Correct Answer: C) 1

15. Which operator is used for multiplication in C programming?

A) +
B) *
C) /
D) %

Correct Answer: B) *

16. What is the result of a / b when a = 9 and b = 4 if both are integers?

A) 2.25
B) 2
C) 3
D) 1

Correct Answer: B) 2

17. Which operator is used to find the remainder after division?

A) %
B) /
C) *
D) -

Correct Answer: A) %

18. Which operator checks if two values are equal?

A) !=
B) ==
C) >
D) <

Correct Answer: B) ==

19. Which operator checks if two values are not equal?

A) ==
B) !=
C) >
D) <

Correct Answer: B) !=

20. Which relational operator checks if the left operand is greater than the right operand?

A) ==
B) >
C) <
D) !=

Correct Answer: B) >

21. Which operator checks if the left operand is less than the right operand?

A) ==
B) >
C) <
D) >=

Correct Answer: C) <

22. What does the >= operator check?

A) If the left operand is greater than or equal to the right operand
B) If the left operand is less than or equal to the right operand
C) If the left operand is greater than the right operand
D) If the left operand is less than the right operand

Correct Answer: A) If the left operand is greater than or equal to the right operand

23. What does the <= operator check?

A) If the left operand is greater than or equal to the right operand
B) If the left operand is less than or equal to the right operand
C) If the left operand is greater than the right operand
D) If the left operand is less than the right operand

Correct Answer: B) If the left operand is less than or equal to the right operand

24. What is the output of the following code:

                printf("%d == %d is %d \n", a, b, a == b);

if a = 5 and b = 5?

A) 5 == 5 is 1
B) 5 == 5 is 0
C) 5 == 5 is true
D) 5 == 5 is false

Correct Answer: A) 5 == 5 is 1

25. Which logical operator represents AND operation in C?

A) &&
B) ||
C) !
D) !=

Correct Answer: A) &&

26. Which logical operator represents OR operation in C?

A) &&
B) ||
C) !
D) ==

Correct Answer: B) ||

27. Which logical operator represents NOT operation in C?

A) &&
B) ||
C) !
D) !=

Correct Answer: C) !

28. What is the result of the expression (a == b) && (c > b) if a = 5, b = 5, and c = 10?

A) 0
B) 1
C) 5
D) 10

Correct Answer: B) 1

29. What does the expression !(a == b) return when a = 5 and b = 5?

A) 0
B) 1
C) 5
D) 10

Correct Answer: A) 0

30. What is the output of (a != b) || (c < b) if a = 5, b = 5, and c = 10?

A) 0
B) 1
C) 5
D) 10

Correct Answer: A) 0

31. Which assignment operator adds the right operand to the left operand and assigns the result to the left operand?

A) -=
B) +=
C) *=
D) /=

Correct Answer: B) +=

32. Which assignment operator is used to subtract and assign the result?

A) -=
B) +=
C) *=
D) /=

Correct Answer: A) -=

33. Which assignment operator multiplies the left operand with the right operand and assigns the result to the left operand?

A) -=
B) +=
C) *=
D) /=

Correct Answer: C) *=

34. What is the output of the following code:

                int a = 5, c; 
                c = a; 
                c += a; 
                printf("%d", c);

A) 5
B) 10
C) 25
D) 0

Correct Answer: B) 10

35. Which assignment operator divides the left operand by the right operand and assigns the result to the left operand?

A) /=
B) +=
C) %=
D) *=

Correct Answer: A) /=

36. Which assignment operator is used to take modulus and assign the result?

A) %=
B) /=
C) *=
D) +=

Correct Answer: A) %=

37. What is the output of the following code:

                int a = 5, c; 
                c = a; 
                c %= a; 
                printf("%d", c);

A) 5
B) 0
C) 25
D) 10

Correct Answer: B) 0

2.3.3 - Bitwise, Conditional and Miscellanous Operators.

38. Which operator in C is used to perform a bitwise AND operation on two numbers?

A) |
B) ^
C) &
D) ~

Correct Answer: C) &

39. What is the output of the following C code:

     #include 

     int main() {
         int a = 12, b = 25;
         printf("Output = %d", a & b);
         return 0;
     }

A) 37
B) 8
C) 12
D) 25

Correct Answer: B) 8

40. What does the bitwise OR operator ( | ) do in C?

A) Sets bits that are 1 in either operand
B) Clears bits that are 0 in both operands
C) Inverts all bits
D) Shifts bits to the right

Correct Answer: A) Sets bits that are 1 in either operand

41. What is the output of the following C code:

                #include 
            
                int main() {
                    int a = 12, b = 25;
                    printf("Output = %d", a | b);
                    return 0;
                }

A) 8
B) 37
C) 25
D) 12

Correct Answer: B) 37

42. Which operator performs a bitwise XOR operation in C?

A) &
B) |
C) ^
D) ~

Correct Answer: C) ^

43. What is the result of a bitwise XOR operation between 12 and 25 in C?

        #include 
    
        int main() {
            int a = 12, b = 25;
            printf("Output = %d", a ^ b);
            return 0;
        }

A) 1
B) 37
C) 21
D) 25

Correct Answer: C) 21

44. Which operator in C shifts the bits of a number to the left?

A) >>
B) <<
C) &
D) ^

Correct Answer: B) <<

45. Which operator in C shifts the bits of a number to the right?

A) >>
B) <<
C) &
D) ^

Correct Answer: A) >>

46. What is the output of the following code snippet for right shift operation in C?

#include 
int main() {
    int num = 212, i;
    for (i = 0; i <= 2; ++i) {
        printf("Right shift by %d: %d\n", i, num >> i);
    }
    return 0;
}

A) 212, 106, 53
B) 0, 1, 2
C) 1, 2, 4
D) 106, 53, 26

Correct Answer: A) 212, 106, 53

47. What is the output of the following code snippet for left shift operation in C?

#include 
int main() {
    int num = 212, i;
    for (i = 0; i <= 2; ++i) {
        printf("Left shift by %d: %d\n", i, num << i);
    }
    return 0;
}

A) 212, 424, 848
B) 0, 1, 2
C) 848, 424, 212
D) 53, 106, 212

Correct Answer: A) 212, 424, 848

48. Which operator in C inverts all bits of a number?

A) &
B) |
C) ^
D) ~

Correct Answer: D) ~

49. What is the output of the following code using the bitwise NOT operator?

                #include 
            
                int main() {
                    printf("Output = %d\n", ~35);
                    printf("Output = %d\n", ~-12);
                    return 0;
                }

A) -36, 11
B) 35, -12
C) 36, 12
D) -35, 12

Correct Answer: A) -36, 11

50. What is the ternary operator (also called the conditional operator) used for in C?

A) Comparing three numbers
B) Repeating a block of code
C) Making decisions between two values based on a condition
D) Swapping values between two variables

Correct Answer: C) Making decisions between two values based on a condition

51. What is the output of the following C code using the conditional (ternary) operator?

#include 
int main() {
    int age;
    printf("Enter your age: ");
    scanf("%d", &age);
    (age >= 18) ? printf("You can vote") :
     printf("You cannot vote");
    return 0;
}

A) You can vote
B) You cannot vote
C) Error
D) Depends on the input

Correct Answer: D) Depends on the input

52. Which operator returns the size of a variable in C?

A) *
B) &
C) sizeof
D) ~

Correct Answer: C) sizeof

53. What is the output of the following C code using the sizeof operator?

 #include 
 int main() {
     int a = 5;
     printf("Size of a = %lu\n", sizeof(a));
     return 0;
 }

A) 2
B) 4
C) 8
D) 1

Correct Answer: B) 4

54. What does the & operator do in C when applied to a variable?

A) Returns the size of the variable
B) Returns the value stored in the variable
C) Returns the address of the variable
D) Inverts all the bits of the variable

Correct Answer: C) Returns the address of the variable

55. Which operator in C is used as a pointer dereference operator to access the value at a given address?

A) &
B) *
C) sizeof
D) ^

Correct Answer: B) *

56. What is the output of the following C code using pointer dereferencing?

 #include 
 void main() {
     int i = 5;
     int *ptr;
     ptr = &i;
     printf("Value of *ptr is %d.\n", *ptr);
 }

A) 5
B) Address of i
C) 0
D) Undefined

Correct Answer: A) 5

2.3.4 - Operators Precedence and Associativity.

57. Which of the following operators has the highest precedence?

(A) + (addition)
(B) * (multiplication)
(C) = (assignment)
(D) || (logical OR)

Correct Answer: (B) * (multiplication).

58. How will the expression 2 + 3 * 4 be evaluated based on operator precedence?

(A) (2 + 3) * 4
(B) 2 + (3 * 4)
(C) (2 * 3) + 4
(D) None of the above

Correct Answer: (B) 2 + (3 * 4).

59. Which operator has the lowest precedence among the following?

(A) +
(B) *
(C) ||
(D) =

Correct Answer: (D) =.

60. What is the result of the expression (2 + 3) * 4 when parentheses are used to change precedence?

(A) 14
(B) 20
(C) 12
(D) 24

Correct Answer: (B) 20.

61. What is the associativity of the assignment operator (=) in the expression x = y = z?

(A) Left-to-right
(B) Right-to-left
(C) No associativity
(D) Top-to-bottom

Correct Answer: (B) Right-to-left.

62. In the expression 2 + 3 + 4, which operation will be performed first due to left-to-right associativity?

(A) (2 + 3) first
(B) (3 + 4) first
(C) (2 + 4) first
(D) The order does not matter

Correct Answer: (A) (2 + 3) first.

63. Which of the following statements is true regarding operator precedence?

(A) Parentheses can override operator precedence.
(B) Addition has higher precedence than multiplication.
(C) Logical AND (&&) has higher precedence than multiplication.
(D) Assignment operators always have the highest precedence.

Correct Answer: (A) Parentheses can override operator precedence.

64. Which operator is left-associative?

(A) * (multiplication)
(B) = (assignment)
(C) || (logical OR)
(D) && (logical AND)

Correct Answer: (A) * (multiplication).

65. In the expression a = b + c * d, which operation is performed first?

(A) b + c
(B) a = b
(C) c * d
(D) None of the above

Correct Answer: (C) c * d.

66. What is the associativity of the logical OR (||) operator?

(A) Left-to-right
(B) Right-to-left
(C) No associativity
(D) Top-to-bottom

Correct Answer: (A) Left-to-right.