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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
const copyToClipboard = str => {const el = document.createElement('textarea');el.value = str;el.setAttribute('readonly', '');el.style.position = 'absolute';el.style.left = '-9999px';document.body.appendChild(el);const selected =document.getSelection().rangeCount > 0? document.getSelection().getRangeAt(0): false;el.select();document.execCommand('copy');document.body.removeChild(el);if (selected) {document.getSelection().removeAllRanges();document.getSelection().addRange(selected);}};copyToClipboard('Lorem ipsum'); // 'Lorem ipsum' copied to clipboard.
class DoublyLinkedList {constructor() {this.nodes = [];}get size() {return this.nodes.length;}get head() {return this.size ? this.nodes[0] : null;}get tail() {return this.size ? this.nodes[this.size - 1] : null;}insertAt(index, value) {const previousNode = this.nodes[index - 1] || null;const nextNode = this.nodes[index] || null;const node = { value, next: nextNode, previous: previousNode };if (previousNode) previousNode.next = node;if (nextNode) nextNode.previous = node;this.nodes.splice(index, 0, node);}insertFirst(value) {this.insertAt(0, value);}insertLast(value) {this.insertAt(this.size, value);}getAt(index) {return this.nodes[index];}removeAt(index) {const previousNode = this.nodes[index - 1] || null;const nextNode = this.nodes[index + 1] || null;if (previousNode) previousNode.next = nextNode;if (nextNode) nextNode.previous = previousNode;return this.nodes.splice(index, 1);}clear() {this.nodes = [];}reverse() {this.nodes = this.nodes.reduce((acc, { value }) => {const nextNode = acc[0] || null;const node = { value, next: nextNode, previous: null };if (nextNode) nextNode.previous = node;return [node, ...acc];}, []);}*[Symbol.iterator]() {yield* this.nodes;}}const list = new DoublyLinkedList();list.insertFirst(1);list.insertFirst(2);list.insertFirst(3);list.insertLast(4);list.insertAt(3, 5);list.size; // 5list.head.value; // 3list.head.next.value; // 2list.tail.value; // 4list.tail.previous.value; // 5[...list.map(e => e.value)]; // [3, 2, 1, 5, 4]list.removeAt(1); // 2list.getAt(1).value; // 1list.head.next.value; // 1[...list.map(e => e.value)]; // [3, 1, 5, 4]list.reverse();[...list.map(e => e.value)]; // [4, 5, 1, 3]list.clear();list.size; // 0
const euclideanDistance = (a, b) =>Math.hypot(...Object.keys(a).map(k => b[k] - a[k]));euclideanDistance([1, 1], [2, 3]); // ~2.2361euclideanDistance([1, 1, 1], [2, 3, 2]); // ~2.4495
//QM Helper by Leif Messinger//Groups numbers by number of bits and shows their binary representations.//To be used on x.comconst minterms = prompt("Enter your minterms separated by commas").split(",").map(x => parseInt(x.trim()));const maxNumBits = minterms.reduce(function(a, b) {return Math.max(a, Math.log2(b));});const bitGroups = [];for(let i = 0; i < maxNumBits; ++i){bitGroups.push([]);}for(const minterm of minterms){let outputString = (minterm+" ");//Count the bitslet count = 0;for (var i = maxNumBits; i >= 0; --i) {if((minterm >> i) & 1){++count;outputString += "1";}else{outputString += "0";}}bitGroups[count].push(outputString);}document.body.textContent = "";document.body.style.setProperty("white-space", "pre");for(const group of bitGroups){for(const outputString of group){document.body.textContent += outputString + "\r\n";}}
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)];};quickSort([1, 6, 1, 5, 3, 2, 1, 4]); // [1, 1, 1, 2, 3, 4, 5, 6]