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compact object

Nov 19, 2022CodeCatch
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levenshtein distance

Nov 19, 2022CodeCatch

0 likes • 1 view

const levenshteinDistance = (s, t) => {
if (!s.length) return t.length;
if (!t.length) return s.length;
const arr = [];
for (let i = 0; i <= t.length; i++) {
arr[i] = [i];
for (let j = 1; j <= s.length; j++) {
arr[i][j] =
i === 0
? j
: Math.min(
arr[i - 1][j] + 1,
arr[i][j - 1] + 1,
arr[i - 1][j - 1] + (s[j - 1] === t[i - 1] ? 0 : 1)
);
}
}
return arr[t.length][s.length];
};
levenshteinDistance('duck', 'dark'); // 2

Scrape twitter

Sep 2, 2023LeifMessinger

0 likes • 11 views

//Allegedly never tested on the twitter website
function 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 second
window.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 = filename
a.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

Timer

Feb 5, 2021LeifMessinger

0 likes • 2 views

class Timer{
start(){
this.startTime = Date.now();
}
stop(){
const dt = Date.now() - this.startTime;
console.log(dt);
return dt;
}
getExecTime(fun, asynchronous){
return asynchronous ? this.getAsyncExecTime(fun) : this.getSyncExecTime(fun);
}
getSyncExecTime(fun){
this.start();
fun();
return this.stop();
}
async getAsyncExecTime(fun){
this.start();
await fun();
return this.stop();
}
static average(fun, numTimes, asynchronous = false){
const times = [];
const promises = [];
let timer = new Timer();
if(asynchronous){
for(let i = 0; i < numTimes; i++){
timer.getAsyncExecTime(fun);
}
}else{
for(let i = 0; i < numTimes; i++){
timer.getSyncExecTime(fun);
}
}
return (times => times.reduce(((sum, acc) => sume + acc), 0) / times.length);
}
static async timeAsync(fun, numTimes){
if(numTimes <= 1) return new Timer().getAsyncExecTime(fun);
const promises = [];
let timer = new Timer(true);
for(let i = 0; i < numTimes; i++){
promises.push(fun().catch((e)=>{}));
}
try{
await Promise.all(promises).catch((e)=>{});
}catch(e){
//do absolutely nothing
}
return timer.stop();
}
constructor(start = false){
if(start) this.start();
}
}

LeetCode Product Except Self

Sep 13, 2023C S

0 likes • 11 views

/**
* @param {number[]} nums
* @return {number[]}
*/
var productExceptSelf = function(nums) {
var output = [];
var leftMult = 1;
var rightMult = 1;
for (var i=nums.length - 1; i >= 0; i--) {
output[i] = rightMult;
rightMult *= nums[i];
console.log({output: JSON.stringify(output), i})
}
for (var j=0; j < nums.length; j++) {
output[j] *= leftMult;
leftMult *= nums[j];
console.log({output: JSON.stringify(output), j})
}
return output;
};
console.log(productExceptSelf([1, 2, 3, 4]))

React Short Circuit Evaluation

Feb 3, 2021C S

0 likes • 1 view

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

greatest common denominator

Nov 19, 2022CodeCatch

0 likes • 0 views

const gcd = (...arr) => {
const _gcd = (x, y) => (!y ? x : gcd(y, x % y));
return [...arr].reduce((a, b) => _gcd(a, b));
};
gcd(8, 36); // 4
gcd(...[12, 8, 32]); // 4