Conditional Statements & Loops
Difficulty: easy
Overview
if/else, switch, and the ternary operator (?:) control branching. The nullish coalescing operator (??) returns the right operand only when the left is null or undefined — unlike || which triggers on any falsy value. for, while, and do-while are the primary loops. for...of iterates over iterable values; for...in iterates over enumerable property keys.
Practice Linked Questions
Q1. What does the nullish coalescing operator (`??`) return?
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Q2. What is the output of the following code? ```js let x = 5; console.log(x > 3 ? "big" : "small"); ```
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Q3. Which of the following values are falsy in JavaScript? (More than one answer may be correct.)
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Q4. What is the output? ```js let i = 0; while (i < 3) { i++; } console.log(i); ```
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Q5. What is the difference between `for...of` and `for...in`?
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Q6. What does the logical OR (`||`) operator return?
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