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arithmetic progression

0 likes • Nov 19, 2022
JavaScript
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K-means clustering

CodeCatch
0 likes • Nov 19, 2022
JavaScript
const kMeans = (data, k = 1) => {
const centroids = data.slice(0, k);
const distances = Array.from({ length: data.length }, () =>
Array.from({ length: k }, () => 0)
);
const classes = Array.from({ length: data.length }, () => -1);
let itr = true;
while (itr) {
itr = false;
for (let d in data) {
for (let c = 0; c < k; c++) {
distances[d][c] = Math.hypot(
...Object.keys(data[0]).map(key => data[d][key] - centroids[c][key])
);
}
const m = distances[d].indexOf(Math.min(...distances[d]));
if (classes[d] !== m) itr = true;
classes[d] = m;
}
for (let c = 0; c < k; c++) {
centroids[c] = Array.from({ length: data[0].length }, () => 0);
const size = data.reduce((acc, _, d) => {
if (classes[d] === c) {
acc++;
for (let i in data[0]) centroids[c][i] += data[d][i];
}
return acc;
}, 0);
for (let i in data[0]) {
centroids[c][i] = parseFloat(Number(centroids[c][i] / size).toFixed(2));
}
}
}
return classes;
};
kMeans([[0, 0], [0, 1], [1, 3], [2, 0]], 2); // [0, 1, 1, 0]

Simple Express Server

CodeCatch
0 likes • Oct 15, 2022
JavaScript
const express = require('express')
const app = express()
const port = 3000
app.get('/', (req, res) => {
res.send('Hello World!')
})
app.listen(port, () => {
console.log(`Example app listening on port ${port}`)
})

native data structures

CodeCatch
0 likes • Nov 19, 2022
JavaScript
const nums = [1, 2, 3];
const strs = Array.from('est');
nums.push(6);
nums.push(4, 9);
strs.unshift('t');
nums.length; // 6
nums[nums.length - 1]; // 9
strs[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); // 25
strs.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; // 5
nums.has(4); // true
nums.delete(4);
nums.has(4); // false
[...nums]; // [1, 2, 3, 5]
nums.clear();
nums.size; // 0
const items = new Map([
[1, { name: 'John' }],
[2, { name: 'Mary' }]
]);
items.set(4, { name: 'Alan' });
items.set(2, { name: 'Jeff' });
items.size; // 3
items.has(4); // true
items.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

Reddit Regex Comment Upvoter

ThiccDaddyLOAF
0 likes • May 17, 2021
JavaScript
//Upvotes comments according to a regex pattern. I tried it out on https://www.reddit.com/r/VALORANT/comments/ne74n4/please_admire_this_clip_precise_gunplay_btw/
//Known bugs:
//If a comment was already upvoted, it gets downvoted
//For some reason, it has around a 50-70% success rate. The case insensitive bit works, but I think some of the query selector stuff gets changed. Still, 50% is good
let comments = document.getElementsByClassName("_3tw__eCCe7j-epNCKGXUKk"); //Comment class
let commentsToUpvote = [];
const regexToMatch = /wtf/gi;
for(let comment of comments){
let text = comment.querySelector("._1qeIAgB0cPwnLhDF9XSiJM"); //Comment content class
if(text == undefined){
continue;
}
text = text.textContent;
if(regexToMatch.test(text)){
console.log(text);
commentsToUpvote.push(comment);
}
}
function upvote(comment){
console.log(comment.querySelector(".icon-upvote")); //Just showing you what it's doing
comment.querySelector(".icon-upvote").click();
}
function slowRecurse(){
let comment = commentsToUpvote.pop(); //It's gonna go bottom to top but whatever
if(comment != undefined){
upvote(comment);
setTimeout(slowRecurse,500);
}
}
slowRecurse();

Zybooks?

ThiccDaddyLOAF
0 likes • Oct 29, 2020
JavaScript
questions = Array.from(document.querySelectorAll(".multiple-choice-question"));
async function hackRadio(question){
if(question.querySelector(".question-chevron").getAttribute("aria-label") == "Question completed") return;
let answerChoices = question.querySelectorAll(".zb-radio-button");
async function guess(answerChoice){
answerChoice.querySelector("label").click();
}
let pause = 0;
for(let answerChoice of answerChoices){
setTimeout(()=>{guess(answerChoice)},pause); //No need to check given that it will record the correct answer anyways.
pause += 1000;
}
}
for(let question of questions){
hackRadio(question);
}
questions = Array.from(document.querySelectorAll(".short-answer-question"));
async function hackShortAnswer(question){
if(question.querySelector(".question-chevron").getAttribute("aria-label") == "Question completed") return;
question.querySelector("textarea").value = question.querySelector(".forfeit-answer").textContent;
//question.querySelector(".check-button").click(); They are smart bastards
}
for(let question of questions){
const showAnswerButton = question.querySelector(".show-answer-button");
showAnswerButton.click();
showAnswerButton.click();
hackShortAnswer(question);
}

bucket sort

CodeCatch
0 likes • Nov 19, 2022
JavaScript
const bucketSort = (arr, size = 5) => {
const min = Math.min(...arr);
const max = Math.max(...arr);
const buckets = Array.from(
{ length: Math.floor((max - min) / size) + 1 },
() => []
);
arr.forEach(val => {
buckets[Math.floor((val - min) / size)].push(val);
});
return buckets.reduce((acc, b) => [...acc, ...b.sort((a, b) => a - b)], []);
};
bucketSort([6, 3, 4, 1]); // [1, 3, 4, 6]