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LESSON 189 OF 410 · NESTED LOOPS

Top K Brands V4 - Top K in JavaScript

Practice

Show the top k brands by rating. This is v3's search, repeated k times: find the best brand, mark it as taken, then search again among the brands that are not taken yet, until you have k brands in rank order.

You start with:

const brands = ["TechPro", "MegaCorp", "Quantum", "NeoByte", "Zenith"];
const ratings = [4, 5, 3, 5, 4];
const k = 3;

Build:

1. MegaCorp (5)
2. NeoByte (5)
3. TechPro (4)

Rules:

  • Repeat v3's search k times. Each round looks only at brands that are not taken yet and picks the one with the highest rating, then marks it as taken (one true/false flag per brand).
  • Ties go to the brand listed first: keep the first brand you find and replace it only on a strictly higher rating.
  • k is never larger than the number of brands.
  • Each line is "rank. Brand (rating)", starting at rank 1.
  • Print the lines, one per line, with console.log(...).

Start with the two declarations const used = new Array(ratings.length).fill(false); and const lines = [];. A flag tells whether that position is already taken.

Each round is v3's search: nothing found yet, scan every position, skip taken ones, keep the first candidate and replace it only on a strictly higher rating. Then mark the winner as taken and add its line.

const brands = ["TechPro", "MegaCorp", "Quantum", "NeoByte", "Zenith"];
const ratings = [4, 5, 3, 5, 4];
const k = 3;

const used = new Array(ratings.length).fill(false);
const lines = [];
for (let rank = 1; rank <= k; rank++) {
    let bestIndex = -1;
    for (let i = 0; i < ratings.length; i++) {
        if (!used[i]) {
            if (bestIndex === -1 || ratings[i] > ratings[bestIndex]) {
                bestIndex = i;
            }
        }
    }
    used[bestIndex] = true;
    lines.push(rank + ". " + brands[bestIndex] + " (" + ratings[bestIndex] + ")");
}
console.log(lines.join("\n"));

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