• Nov 19, 2022 •CodeCatch
0 likes • 1 view
class TreeNode { constructor(key, value = key, parent = null) { this.key = key; this.value = value; this.parent = parent; this.children = []; } get isLeaf() { return this.children.length === 0; } get hasChildren() { return !this.isLeaf; } } class Tree { constructor(key, value = key) { this.root = new TreeNode(key, value); } *preOrderTraversal(node = this.root) { yield node; if (node.children.length) { for (let child of node.children) { yield* this.preOrderTraversal(child); } } } *postOrderTraversal(node = this.root) { if (node.children.length) { for (let child of node.children) { yield* this.postOrderTraversal(child); } } yield node; } insert(parentNodeKey, key, value = key) { for (let node of this.preOrderTraversal()) { if (node.key === parentNodeKey) { node.children.push(new TreeNode(key, value, node)); return true; } } return false; } remove(key) { for (let node of this.preOrderTraversal()) { const filtered = node.children.filter(c => c.key !== key); if (filtered.length !== node.children.length) { node.children = filtered; return true; } } return false; } find(key) { for (let node of this.preOrderTraversal()) { if (node.key === key) return node; } return undefined; } } const tree = new Tree(1, 'AB'); tree.insert(1, 11, 'AC'); tree.insert(1, 12, 'BC'); tree.insert(12, 121, 'BG'); [...tree.preOrderTraversal()].map(x => x.value); // ['AB', 'AC', 'BC', 'BCG'] tree.root.value; // 'AB' tree.root.hasChildren; // true tree.find(12).isLeaf; // false tree.find(121).isLeaf; // true tree.find(121).parent.value; // 'BC' tree.remove(12); [...tree.postOrderTraversal()].map(x => x.value); // ['AC', 'AB']
• Mar 11, 2021 •C S
0 likes • 3 views
import { configureStore } from "@reduxjs/toolkit"; import { combineReducers } from "redux"; import profile from "./profile"; import auth from "./auth"; import alert from "./alert"; const reducer = combineReducers({ profile, auth, alert, }); const store = configureStore({ reducer }); export default store;
// There are n rings and each ring is either red, green, or blue. The rings are distributed across ten rods labeled from 0 to 9. // You are given a string rings of length 2n that describes the n rings that are placed onto the rods. Every two characters in rings forms a color-position pair that is used to describe each ring where: // The first character of the ith pair denotes the ith ring's color ('R', 'G', 'B'). // The second character of the ith pair denotes the rod that the ith ring is placed on ('0' to '9'). // For example, "R3G2B1" describes n == 3 rings: a red ring placed onto the rod labeled 3, a green ring placed onto the rod labeled 2, and a blue ring placed onto the rod labeled 1. // Return the number of rods that have all three colors of rings on them. let rings = "B0B6G0R6R0R6G9"; var countPoints = function(rings) { let sum = 0; // Always 10 Rods for (let i = 0; i < 10; i++) { if (rings.includes(`B${i}`) && rings.includes(`G${i}`) && rings.includes(`R${i}`)) { sum+=1; } } return sum; }; console.log(countPoints(rings));
• Oct 15, 2022 •CodeCatch
3 likes • 4 views
const MongoClient = require('mongodb').MongoClient; const assert = require('assert'); // Connection URL const url = 'mongodb://localhost:27017'; // Database Name const dbName = 'myproject'; // Use connect method to connect to the server MongoClient.connect(url, function(err, client) { assert.equal(null, err); console.log("Connected successfully to server"); const db = client.db(dbName); client.close(); });
• Feb 3, 2021 •C S
0 likes • 2 views
import React, { useState } from 'react' import Welcome from '../components/Welcome' function About() { const [showWelcome, setShowWelcome] = useState(false) return ( <div> {showWelcome ? <Welcome /> : null} </div> <div> {showWelcome && <Welcome /> } </div> ) } export default App
• Jan 26, 2023 •AustinLeath
0 likes • 6 views
function printHeap(heap, index, level) { if (index >= heap.length) { return; } console.log(" ".repeat(level) + heap[index]); printHeap(heap, 2 * index + 1, level + 1); printHeap(heap, 2 * index + 2, level + 1); } //You can call this function by passing in the heap array and the index of the root node, which is typically 0, and level = 0. let heap = [3, 8, 7, 15, 17, 30, 35, 2, 4, 5, 9]; printHeap(heap,0,0)