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const binomialCoefficient = (n, k) => {if (Number.isNaN(n) || Number.isNaN(k)) return NaN;if (k < 0 || k > n) return 0;if (k === 0 || k === n) return 1;if (k === 1 || k === n - 1) return n;if (n - k < k) k = n - k;let res = n;for (let j = 2; j <= k; j++) res *= (n - j + 1) / j;return Math.round(res);};binomialCoefficient(8, 2); // 28
//Retries maxRetries number of times, meaning that if you have 0, then it'll run the function once.async function retryPromise(promiseFn, maxRetries = 3, delayOffset = 0, delayRandomRange = 0) {return new Promise((resolve, reject) => {promiseFn().then(resolve, (error) => { //On errorif (maxRetries <= 0) {return reject(error);} else {if(delayRandomRange * Math.random() + delayOffset < 1.0){return retryPromise(promiseFn, maxRetries - 1, delayOffset, delayRandomRange).then(resolve, reject);}else{return new Promise((resolveTwo, rejectTwo) => {setTimeout(() => {return retryPromise(promiseFn, maxRetries - 1, delayOffset, delayRandomRange).then(resolveTwo, rejectTwo);}, delayRandomRange * Math.random() + delayOffset);}).then(resolve, reject);}}});});}//Tests for that function.//Returns a function that will fail numTimes times, then will return aValuefunction functionThatReturnsAFunctionThatFailsACoupleTimes(numTimes, aValue){return async function(){if(numTimes == 0){return aValue;}numTimes--;throw false;};}const SMALL_NUMBER = 10;function testTest(failNumberOfTimes){let functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(failNumberOfTimes, true);//Test my testfor(let i = 0; i < (failNumberOfTimes * 2); ++i){function evalTest(val){let testTestFailedReason = "";if(val === undefined){testTestFailedReason = "Test test returned undefined for some reason.";}if((i + 1) > failNumberOfTimes){if(val === true){//We're good}else{testTestFailedReason = "Test test didn't return true when it should have.";}}else{if(val === false){//We're good}else{testTestFailedReason = "Test test didn't return false when it should have.";}}testTestFailedReason = testTestFailedReason || "Test test passed test case";console.log(testTestFailedReason, "at index", i, "where the function returned", val);}functionThatFailsACoupleTimes().then(evalTest, evalTest)};}testTest(SMALL_NUMBER);let testCaseCounter = 1;const throwsNoError = [(val)=>{if(val == true){console.log("Passed test case " + (testCaseCounter++));}else{console.error("Unexpected return value", val);}},()=>{console.error("It wasn't supposed to fail!")}]const throwsError = [(val)=>{console.error("It wasn't supposed to succeed!", val);},(val)=>{if(val == false){console.log("Passed test case " + (testCaseCounter++));}else{console.error("Unexpected return value", val);}}];//Runs SMALL_NUMBER times, because SMALL_NUMBER - 1 is the number of retries after the first onelet functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);retryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 1).then(...throwsNoError)functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);//Runs SMALL_NUMBER - 1 times, because SMALL_NUMBER - 2 is the number of retries after the first oneretryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 2).then(...throwsError)//Testing the delay. You'll have to wait a bit too.functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);//Runs SMALL_NUMBER times, because SMALL_NUMBER - 1 is the number of retries after the first oneretryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 1, 500, 500).then(...throwsNoError)functionThatFailsACoupleTimes = functionThatReturnsAFunctionThatFailsACoupleTimes(SMALL_NUMBER - 1, true);//Runs SMALL_NUMBER - 1 times, because SMALL_NUMBER - 2 is the number of retries after the first oneretryPromise(functionThatFailsACoupleTimes, SMALL_NUMBER - 2, 500, 500).then(...throwsError)
const gcd = (...arr) => {const _gcd = (x, y) => (!y ? x : gcd(y, x % y));return [...arr].reduce((a, b) => _gcd(a, b));};gcd(8, 36); // 4gcd(...[12, 8, 32]); // 4
const rectSize = 15; // Size of the color boxconst spacing = 5; // Space between legend itemslet legend = canvas.append('g').attr('class','chart-legend').attr('transform', `translate(${0}, ${height + 3})`);// Sample data for the legendconst legendData = [{ label: 'low', color: '#1f77b4' },{ label: 'medium', color: '#ff7f0e' },{ label: 'high', color: '#2ca02c' },{ label: 'very high', color: '#2ca02c' }];legend.selectAll('g').data(legendData).join('g').attr('class', 'legend-item').each(function (d, i) {const legendItem = d3.select(this);console.log(d.label)console.log(d.label?.length)let labelWidth = (d.label.length * 5) + 7 + 15var bbox = legendItem.node().getBBox()var width = bbox.widthconsole.log(width)// Add rectangle for colorlegendItem.append('rect').attr('width', rectSize).attr('height', rectSize).attr('fill', d.color);// Add labellegendItem.append('text').attr('x', rectSize + spacing) // Position text to the right of the rectangle.attr('y', rectSize / 2) // Align text vertically with the rectangle.attr('dy', '.35em') // Adjust vertical alignment.attr('text-anchor', 'start') // Align text to the start.text(d.label).attr('fill', 'black'); // Optional: Text color// legendItem.attr('transform', `translate(${i * (rectSize + spacing + labelWidth)}, 0)`) // Position each item horizontally});const legendItems_spacing = 12var legendLength = 0legend.selectAll('.legend-item').each(function(d,i) {d3.select(this).attr('transform',function() {var bbox = d3.select(this).node().getBBox()var width = bbox.width// if (width == 0) width = (d.text.length * 5) +15 // not in dom yetlet startingPosition = 0if (i > 0) {startingPosition = legendLength}legendLength += width + legendItems_spacing// return `translate(${xx - (width + 30)},0$)`return `translate(${startingPosition},0)`})})
//Allegedly never tested on the twitter websitefunction scrapeScreen(){let articles = Array.from(document.getElementsByTagName("article"));let results = [];for(let tweet of articles){const isAnAd = Array.from(tweet.querySelectorAll("span")).map((e)=>e.textContent).includes("Ad");if(isAnAd){//console.log(tweet, "is an ad. Skipping...");continue;}const userName = tweet.querySelector("[data-testid='User-Name'] > div:nth-child(2) > div > div")?.textContent;const tweetContent = tweet.querySelector("[data-testid='tweetText']")?.textContent;const timeStamp = tweet.querySelector("time")?.getAttribute("datetime");const tweetLink = tweet.querySelector("time")?.parentElement?.getAttribute("href");if((!userName) || (!tweetContent)) continue;results.push({username: userName,tweetText: tweetContent,timeStamp: timeStamp,tweetLink: tweetLink});}return results;}let scraped = scrapeScreen();setInterval(()=>{scraped = scraped.concat(scrapeScreen().filter((tweet)=>{for(let scrapedTweet of scraped){if(scrapedTweet.username == tweet.username && scrapedTweet.tweetText == tweet.tweetText) return false;}return true;}));}, 500); //Scrape everything on the screen twice a secondwindow.scrollIntervalId = setInterval(function(){window.scrollBy(0, 1000);}, 500); //Scroll for me//http://bgrins.github.io/devtools-snippets/#console-save(function(console){console.save = function(data, filename){if(!data) {console.error('Console.save: No data')return;}if(!filename) filename = 'console.json'if(typeof data === "object"){data = JSON.stringify(data, undefined, '\t')}var blob = new Blob([data], {type: 'text/json'}),e = document.createEvent('MouseEvents'),a = document.createElement('a')a.download = filenamea.href = window.URL.createObjectURL(blob)a.dataset.downloadurl = ['text/json', a.download, a.href].join(':')e.initMouseEvent('click', true, false, window, 0, 0, 0, 0, 0, false, false, false, false, 0, null)a.dispatchEvent(e)}})(console)setTimeout(()=>{clearTimeout(window.scrollIntervalId);delete window.scrollIntervalId;console.save(scraped, "TwitterScrape" + Date.now() + ".json");}, 60 * 1000 * 20); //Twenty minutes
const nums = [1, 2, 3];const strs = Array.from('est');nums.push(6);nums.push(4, 9);strs.unshift('t');nums.length; // 6nums[nums.length - 1]; // 9strs[0]; // 't'strs[2]; // 's'nums.slice(1, 3); // [2, 3]nums.map(n => n * 2); // [2, 4, 6, 12, 8, 18]nums.filter(n => n % 2 === 0); // [2, 6, 4]nums.reduce((a, n) => a + n, 0); // 25strs.reverse(); // ['t', 's', 'e', 't']strs.join(''); // 'test'const nums = new Set([1, 2, 3]);nums.add(4);nums.add(1);nums.add(5);nums.add(4);nums.size; // 5nums.has(4); // truenums.delete(4);nums.has(4); // false[...nums]; // [1, 2, 3, 5]nums.clear();nums.size; // 0const items = new Map([[1, { name: 'John' }],[2, { name: 'Mary' }]]);items.set(4, { name: 'Alan' });items.set(2, { name: 'Jeff' });items.size; // 3items.has(4); // trueitems.get(2); // { name: 'Jeff' }items.delete(2);items.size; // 2[...items.keys()]; // [1, 4][...items.values()]; // [{ name: 'John' }, { name: 'Alan' }]items.clear();items.size; // 0