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LESSON 195 OF 414 · NESTED LOOPS

Top K Brands V6 - Tie-Break by Review Count in TypeScript

Practice

Rank the top k brands by rating, breaking ties with the review count. This builds on v4's repeated search (not on v5: there is no filtering here); only the comparison gets a second criterion.

You start with:

const brands: string[] = ["TechPro", "MegaCorp", "NeoByte", "Quantum", "Zenith"];
const ratings: number[] = [4, 5, 5, 3, 4];
const reviews: number[] = [200, 150, 500, 100, 300];
const k: number = 3;

Build:

1. NeoByte (5, 500)
2. MegaCorp (5, 150)
3. Zenith (4, 300)

Rules:

  • Rating decides first: the higher rating wins.
  • If two brands have the same rating, the one with more reviews wins.
  • If rating and reviews are both equal, the one listed first wins (the test data has no such pair, but your code must follow the rule).
  • k is never larger than the number of brands.
  • Each line is "rank. Brand (rating, reviews)", starting at rank 1.
  • Print the lines, one per line, with console.log(...).

Start from v4: the same const used: boolean[] = new Array(ratings.length).fill(false); and const lines: string[] = [];, the same two loops. Only the comparison inside the inner loop changes.

Use a chain (if / else if / else if): no candidate yet, take this one; else a higher rating, take this one; else the same rating and more reviews, take this one.

const brands: string[] = ["TechPro", "MegaCorp", "NeoByte", "Quantum", "Zenith"];
const ratings: number[] = [4, 5, 5, 3, 4];
const reviews: number[] = [200, 150, 500, 100, 300];
const k: number = 3;

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

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    Top K Brands V6 in TypeScript

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