Basic Trie implementation and problem solve with Heap - Javascript

trie-heap-words.js

"use strict";

const Heap = require("heap");

class Trie {
    count = 0;
    key = null;
 
    // each node stores a map to its child nodes
    character = {};
    
    insert(key) {
      let curr = this;
      
      for (const c of key) {
        curr.character[c] = curr.character[c] || new Trie();
        curr = curr.character[c];
      }
      
      curr.key = key;
      curr.count++;
    }
    
    preorder (heap) {
      if (this.count > 0) {
        heap.push({key: this.key, count: this.count})
      }
      
      for (const c of Object.values(this.character)) {
        c.preorder(heap);
      }      
    }
}

const keys = ["code", "coder", "coding", "codable", "codec", "codecs", "coded", "codeless", "codec", "codecs", "codependence", "codex", "codify", "codependents", "codes", "code", "coder", "codesign", "codec", "codeveloper", "codrive", "codec", "codecs", "codiscovered"];


const trie = new Trie();
for (const key of keys) {
  trie.insert(key);
}

const heap = new Heap((a, b) => b.count - a.count);
trie.preorder(heap);


console.log(heap)