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React - Lifting State

1 like • Jan 25, 2023
JavaScript
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URL Search Term Generator

JoeCamRoberon
0 likes • Jan 17, 2021
JavaScript
const getSearchTerm = delimiter => {
let searchTerm = "";
for (let i = 1; i < commands.length - 1; i++)
searchTerm = searchTerm + commands[i] + delimiter;
searchTerm += commands[commands.length - 1];
return searchTerm;
};

unzipWith() function

CodeCatch
0 likes • Nov 19, 2022
JavaScript
const unzipWith = (arr, fn) =>
arr
.reduce(
(acc, val) => (val.forEach((v, i) => acc[i].push(v)), acc),
Array.from({
length: Math.max(...arr.map(x => x.length))
}).map(x => [])
)
.map(val => fn(...val));
unzipWith(
[
[1, 10, 100],
[2, 20, 200],
],
(...args) => args.reduce((acc, v) => acc + v, 0)
);
// [3, 30, 300]

Flatten an array

CodeCatch
0 likes • Nov 19, 2022
JavaScript
const flat = arr => [].concat.apply([], arr.map(a => Array.isArray(a) ? flat(a) : a));
// Or
const flat = arr => arr.reduce((a, b) => Array.isArray(b) ? [...a, ...flat(b)] : [...a, b], []);
// Or
// See the browser compatibility at https://caniuse.com/#feat=array-flat
const flat = arr => arr.flat();
// Example
flat(['cat', ['lion', 'tiger']]); // ['cat', 'lion', 'tiger']

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);
}
function printHeap(heap, index, level) {
if (index >= heap.length) {
return;
}
console.log(" ".repeat(level) + heap[index]);
printHeap(heap, 2 * index + 1, level + 1);
printHeap(heap, 2 * index + 2, level + 1);
}
//You can call this function by passing in the heap array and the index of the root node, which is typically 0, and level = 0.
let heap = [3, 8, 7, 15, 17, 30, 35, 2, 4, 5, 9];
printHeap(heap,0,0)

MongoDB Connection

CodeCatch
0 likes • Oct 15, 2022
JavaScript
const MongoClient = require('mongodb').MongoClient;
const assert = require('assert');
// Connection URL
const url = 'mongodb://localhost:27017';
// Database Name
const dbName = 'myproject';
// Use connect method to connect to the server
MongoClient.connect(url, function(err, client) {
assert.equal(null, err);
console.log("Connected successfully to server");
const db = client.db(dbName);
client.close();
});