---
title: "Conditional operator vs if-else; digit sum"
subject: "Computer Programming"
chapter: 5
key: "semester_1/computer_programming:conditional-operator-vs-ifelse"
source: https://www.bctengineer.com/q/semester_1/computer_programming/conditional-operator-vs-ifelse
site: BCT Engineering
---

# Conditional operator vs if-else; digit sum

Computer Programming · Chapter 5: Control statements

- Asked in: 2068 Chaitra, 2 marks
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_1/computer_programming/conditional-operator-vs-ifelse
- Whole chapter: https://www.bctengineer.com/md/semester_1/computer_programming/chapter-5

## Question

Differentiate between conditional operator and if-else statement.

## Short answer

The conditional operator (?:) is an expression that returns a value, compact for simple choices and usable inside larger expressions. The if-else statement is not an expression, cannot be embedded in expressions, and is better for blocks with multiple statements.

## Answer

| Conditional operator (`?:`) | if-else statement |
|---|---|
| An operator that forms an expression and returns a value | A statement; does not return a value |
| Syntax: `x = (cond) ? a : b;` | Syntax: `if (cond) ... else ...` |
| Compact, for simple choices | Better for long or multiple statements in a branch |
| Can be used inside another expression | Cannot be used inside an expression |
| Both branches must be expressions | Branches may contain any statements, loops, declarations |
| Hard to read when nested | Easy to read even when nested |

```c
#include <stdio.h>
int main(void)
{
    int a = 8, b = 3, big, big2;
    big = (a > b) ? a : b;       /* conditional operator */
    if (a > b)                   /* if-else */
        big2 = a;
    else
        big2 = b;
    printf("%d %d\n", big, big2);
    return 0;
}
```
Output:
```text
8 8
```

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Which one returns a value as an expression?
   A. if-else statement
   B. Both
   C. Conditional operator ?:
   D. Neither
   Answer: C. ?: forms an expression; if-else is a statement. (Key point: Value)

2. Which allows any statements, loops and declarations in a branch?
   A. Conditional operator
   B. Both
   C. Neither
   D. if-else
   Answer: D. Branches of ?: must be expressions. (Key point: Branches)

3. Which is hard to read when nested?
   A. Conditional operator
   B. if-else
   C. Both equally
   D. Neither
   Answer: A. Nested ?: becomes unclear. (Key point: Readability)

4. Which is correct for the conditional operator?
   A. x = if (cond) a else b;
   B. x = (cond) ? a : b;
   C. x = cond : a ? b;
   D. x = (cond) a : b;
   Answer: B. Form is cond ? a : b. (Key point: Syntax)

## Related in Computer Programming

- [Compare switch and if-else-if ladder](https://www.bctengineer.com/question.md?key=semester_1%2Fcomputer_programming%3Aswitch-vs-ifelse-ladder) — Computer Programming, chapter 5, asked 2×
- [Syntax of if...else](https://www.bctengineer.com/question.md?key=semester_1%2Fcomputer_programming%3Asyntax-if-else) — Computer Programming, chapter 5
- [Operators; conditional operator](https://www.bctengineer.com/question.md?key=semester_1%2Fcomputer_programming%3Aoperator-conditional) — Computer Programming, chapter 3
- [Sum of digits until single digit](https://www.bctengineer.com/question.md?key=semester_1%2Fcomputer_programming%3Adigit-sum-single-digit) — Computer Programming, chapter 5, asked 2×
- [Nested if with flowchart](https://www.bctengineer.com/question.md?key=semester_1%2Fcomputer_programming%3Anested-if-flowchart) — Computer Programming, chapter 5

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