Loading...
More JavaScript Posts
const quickSort = arr => {const a = [...arr];if (a.length < 2) return a;const pivotIndex = Math.floor(arr.length / 2);const pivot = a[pivotIndex];const [lo, hi] = a.reduce((acc, val, i) => {if (val < pivot || (val === pivot && i != pivotIndex)) {acc[0].push(val);} else if (val > pivot) {acc[1].push(val);}return acc;},[[], []]);return [...quickSort(lo), pivot, ...quickSort(hi)];};console.log(quickSort([1, 6, 1, 5, 3, 2, 1, 4])) // [1, 1, 1, 2, 3, 4, 5, 6]
// Orconst randomColor = () => `#${(~~(Math.random()*(1<<24))).toString(16)}`;console.log(randomColor);
class Graph {constructor(directed = true) {this.directed = directed;this.nodes = [];this.edges = new Map();}addNode(key, value = key) {this.nodes.push({ key, value });}addEdge(a, b, weight) {this.edges.set(JSON.stringify([a, b]), { a, b, weight });if (!this.directed)this.edges.set(JSON.stringify([b, a]), { a: b, b: a, weight });}removeNode(key) {this.nodes = this.nodes.filter(n => n.key !== key);[...this.edges.values()].forEach(({ a, b }) => {if (a === key || b === key) this.edges.delete(JSON.stringify([a, b]));});}removeEdge(a, b) {this.edges.delete(JSON.stringify([a, b]));if (!this.directed) this.edges.delete(JSON.stringify([b, a]));}findNode(key) {return this.nodes.find(x => x.key === key);}hasEdge(a, b) {return this.edges.has(JSON.stringify([a, b]));}setEdgeWeight(a, b, weight) {this.edges.set(JSON.stringify([a, b]), { a, b, weight });if (!this.directed)this.edges.set(JSON.stringify([b, a]), { a: b, b: a, weight });}getEdgeWeight(a, b) {return this.edges.get(JSON.stringify([a, b])).weight;}adjacent(key) {return [...this.edges.values()].reduce((acc, { a, b }) => {if (a === key) acc.push(b);return acc;}, []);}indegree(key) {return [...this.edges.values()].reduce((acc, { a, b }) => {if (b === key) acc++;return acc;}, 0);}outdegree(key) {return [...this.edges.values()].reduce((acc, { a, b }) => {if (a === key) acc++;return acc;}, 0);}}const g = new Graph();g.addNode('a');g.addNode('b');g.addNode('c');g.addNode('d');g.addEdge('a', 'c');g.addEdge('b', 'c');g.addEdge('c', 'b');g.addEdge('d', 'a');g.nodes.map(x => x.value); // ['a', 'b', 'c', 'd'][...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);// ['a => c', 'b => c', 'c => b', 'd => a']g.adjacent('c'); // ['b']g.indegree('c'); // 2g.outdegree('c'); // 1g.hasEdge('d', 'a'); // trueg.hasEdge('a', 'd'); // falseg.removeEdge('c', 'b');[...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);// ['a => c', 'b => c', 'd => a']g.removeNode('c');g.nodes.map(x => x.value); // ['a', 'b', 'd'][...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);// ['d => a']g.setEdgeWeight('d', 'a', 5);g.getEdgeWeight('d', 'a'); // 5
require("dotenv").config();const mongoose = require("mongoose");const db = process.env.MONGO_URI;const connectDB = async () => {try {await mongoose.connect(db, {useNewUrlParser: true,useUnifiedTopology: true,useFindAndModify: false,useCreateIndex: true});console.log("MongoDB Connected");} catch (err) {console.error(err.message);}};module.exports = connectDB;
/*** @param {number[]} nums* @return {boolean}*/var containsDuplicate = function(nums) {return new Set(nums).size !== nums.length};
function Welcome(props) {return <h1>Hello, {props.name}</h1>;}function App() {return (<div><Welcome name="Sara" /><Welcome name="Cahal" /><Welcome name="Edite" /></div>);}ReactDOM.render(<App />,document.getElementById('root'));