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Quick Start

Leaderboard (Ranked Collections)​

import { RedBlackTree } from 'data-structure-typed';

// Descending comparator — highest scores first
const leaderboard = new RedBlackTree<number, string>([
  [100, 'Alice'],
  [85, 'Bob'],
  [92, 'Charlie']
], { comparator: (a, b) => b - a });

// Top-2 via lazy iterator — O(2 log n), no full traversal
const iter = leaderboard.entries();
for (let i = 0; i < 2; i++) {
  const { value: [score, player] } = iter.next();
  console.log(`${score}: ${player}`);
}
// Output: 100: Alice → 92: Charlie

// Update score — O(log n)
leaderboard.delete(85);
leaderboard.set(95, 'Bob');

// Range query — players scoring 90~100, O(log n + k)
const scores90to100 = leaderboard.rangeSearch([90, 100]);

Order-Statistic Tree (Rank Queries)​

import { RedBlackTree } from 'data-structure-typed';

// Enable order-statistic for O(log n) rank operations
const tree = new RedBlackTree<number, string>([
  [100, 'Alice'],
  [85, 'Bob'],
  [92, 'Charlie'],
  [78, 'Diana'],
  [95, 'Eve']
], { comparator: (a, b) => b - a, enableOrderStatistic: true });

// select(k) — find k-th element (0-indexed)
console.log(tree.getByRank(0));  // 100 (1st in tree order)
console.log(tree.getByRank(2));  // 92  (3rd in tree order)

// rank(key) — how many elements before this key?
console.log(tree.getRank(92));   // 2 (2 elements before 92 in tree order)

// rangeByRank(start, end) — pagination
console.log(tree.rangeByRank(0, 2)); // [100, 95, 92] — top 3

// Inverse property: getByRank(getRank(key)) === key
const k = tree.getRank(85);
console.log(tree.getByRank(k));  // 85

Task Queue (Scheduling)​

import { MinPriorityQueue } from 'data-structure-typed';

const tasks = new MinPriorityQueue<{ task: string; priority: number }>(
  [], { comparator: (a, b) => a.priority - b.priority }
);

tasks.add({ task: 'Send email', priority: 3 });
tasks.add({ task: 'Fix critical bug', priority: 1 });
tasks.add({ task: 'Update docs', priority: 2 });

// Process in priority order
while (!tasks.isEmpty()) {
  const next = tasks.poll();
  console.log(next?.task);
}
// Fix critical bug → Update docs → Send email

Fast Autocomplete (Trie)​

import { Trie } from 'data-structure-typed';

const trie = new Trie();
trie.addMany(['apple', 'application', 'app', 'apex']);

console.log(trie.getWords('app')); // ['app', 'apple', 'application']
console.log(trie.hasPrefix('ap')); // true

Next Steps​