Coding Challenge

Remove duplicate numbers from an array using a Set, then sort the unique values and join them into a hyphen-separated string.

Task

Given an array with repeated integers, deduplicate the values, sort them in ascending order, and output the final string joined by hyphens.

Formula

unique = [...new Set(arr)] → unique.sort((a, b) => a - b) → unique.join("-")

Example Code


const arr = [3, 1, 2, 3, 4, 1, 5, 2, 6, 3];

// remove duplicates and sort ascending
const unique = [...new Set(arr)];
const result = unique.sort((a, b) => a - b).join("-");

console.log(result);

Question

What will be logged to the console after running the code above?

Options

1-2-3-4-5-6
3-1-2-4-5-6
1-2-3-4-5-6-3
6-5-4-3-2-1

Hint: Set removes repeated values while keeping first-seen order; sorting happens after deduplication.