Viva questions based on C Decision Making statements with Answers

Viva Questions on C Decision Making Statements with Answers

(if, if-else, nested if, switch, conditional operator)

1. What is a decision-making statement in C?

Answer:

A decision-making statement allows the program to take different actions based on conditions. Examples are if, if-else, nested if, switch, and the conditional (ternary) operator ?:.

2. What is the difference between if and if-else statements?

Answer:

if executes a block of code only if the condition is true.
if-else provides an alternative block of code to execute when the condition is false.

3. Can we use multiple if-else statements in C?

Answer:

Yes, we can use multiple if-else if constructs, also known as ladder if-else, to check multiple conditions sequentially.

4. What is a nested if statement?

Answer:

A nested if means writing an if statement inside another if or else block. It is useful when multiple levels of decision-making are required.

5. How does a switch statement work in C?

Answer:

A switch evaluates an expression and compares it with multiple case labels. When a match is found, the corresponding block is executed until a break statement is encountered.

6. What happens if we don’t use break in a switch case?

Answer:

Without break, the program executes the matched case and then continues executing subsequent cases (fall-through) until it encounters a break or the end of the switch block.

7. Can a switch statement work with floating-point values?

Answer:

No, in C, a switch statement works only with integer and character values, not with float or double.

8. What is the difference between if-else and switch?

Answer:

if-else can handle complex conditions (logical expressions, ranges, multiple conditions).
switch is limited to checking equality of a single expression against constant values but is often faster and more readable.

9. What is the conditional (ternary) operator in C?

Answer:

The conditional operator ?: is a shorthand for if-else.

Example:

int max = (a > b) ? a : b;

This assigns a to max if a > b, otherwise assigns b.

10. Is it possible to use a switch inside another switch?

Answer:

Yes, we can have nested switch statements, but it is not commonly used because it reduces readability.

11. What is the difference between = and == in decision-making?

Answer:

= is the assignment operator (assigns value).
== is the equality operator (compares two values).
Using = instead of == inside conditions is a common error.

12. Can if statements be written without curly braces {}?

Answer:

Yes, if there is only one statement inside the if or else block, curly braces are optional. But for multiple statements, curly braces are required.

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