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linear search

0 likes • Nov 19, 2022 • 0 views
JavaScript
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native data structures

0 likes • Nov 19, 2022 • 0 views
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

permutations

0 likes • Nov 19, 2022 • 0 views
JavaScript
const permutations = arr => {
if (arr.length <= 2) return arr.length === 2 ? [arr, [arr[1], arr[0]]] : arr;
return arr.reduce(
(acc, item, i) =>
acc.concat(
permutations([...arr.slice(0, i), ...arr.slice(i + 1)]).map(val => [
item,
...val,
])
),
[]
);
};
permutations([1, 33, 5]);
// [ [1, 33, 5], [1, 5, 33], [33, 1, 5], [33, 5, 1], [5, 1, 33], [5, 33, 1] ]

Global Variables

0 likes • Oct 29, 2020 • 1 view
JavaScript
let variableSet = JSON.parse('["parent","opener","top","length","frames","closed","location","self","window","document","name","customElements","history","locationbar","menubar","personalbar","scrollbars","statusbar","toolbar","status","frameElement","navigator","origin","external","screen","innerWidth","innerHeight","scrollX","pageXOffset","scrollY","pageYOffset","visualViewport","screenX","screenY","outerWidth","outerHeight","devicePixelRatio","clientInformation","screenLeft","screenTop","defaultStatus","defaultstatus","styleMedia","onsearch",&qu...find","webkitRequestAnimationFrame","webkitCancelAnimationFrame","fetch","btoa","atob","setTimeout","clearTimeout","setInterval","clearInterval","createImageBitmap","close","focus","blur","postMessage","onappinstalled","onbeforeinstallprompt","crypto","indexedDB","webkitStorageInfo","sessionStorage","localStorage","chrome","onpointerrawupdate","speechSynthesis","webkitRequestFileSystem","webkitResolveLocalFileSystemURL","openDatabase","variableSet","TEMPORARY","PERSISTENT","addEventListener","removeEventListener","dispatchEvent"]');
let answer = [];
for(let v in this) if(!variableSet.includes(v)) answer.push(v);
console.log(answer);

bucket sort

0 likes • Nov 19, 2022 • 0 views
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]

Mee6 Spam Calculator

0 likes • Mar 10, 2022 • 1 view
JavaScript
//Use at https://mee6.xyz/leaderboard/732262089447702588
//Higher the spammy stat, the more spammy that person is.
//This is because mee doesn't give experience to people who post more comments in a minute.
function statBlock(title, value){
let elm = document.createElement("div");
elm.className = "leaderboardPlayerStatBlock";
let titleElm = document.createElement("div");
titleElm.className = "leaderboardPlayerStatName";
titleElm.textContent = title;
let valueElm = document.createElement("div");
valueElm.className = "leaderboardPlayerStatValue";
valueElm.textContent = value;
elm.appendChild(titleElm);
elm.appendChild(valueElm);
elm.remove = function(){
this.parentElement.removeChild(this);
}
return elm;
}
for(let player of Array.from(document.getElementsByClassName("leaderboardPlayer"))){
if(player.spamminess) player.spamminess.remove();
let messages = null;
let experience = null;
const statBlockArray = Array.from(player.querySelectorAll(".leaderboardPlayerStatBlock"));
for(let statBlock of statBlockArray){
const statName = statBlock.querySelector(".leaderboardPlayerStatName").textContent;
const text = statBlock.querySelector(".leaderboardPlayerStatValue").textContent;
const number = ((text.includes("k"))? (text.replace("k","") * 1000.0) : +(text));
if(statName.includes("MESSAGES")){
messages = number;
}else if(statName.includes("EXPERIENCE")){
experience = number;
}
}
const stats = player.querySelector(".leaderboardPlayerStats");
const messagesElement = stats.firstChild;
const spamminess = ((messages/experience)*2000.0).toFixed(2);
player.spamminess = stats.insertBefore(statBlock("SPAMMINESS", spamminess), messagesElement);
}

JWT Authentication

CHS
0 likes • Mar 11, 2021 • 0 views
JavaScript
const jwt = require("jsonwebtoken");
const authToken = (req, res, next) => {
const token = req.headers["x-auth-token"];
try {
req.user = jwt.verify(token, process.env.ACCESS_TOKEN_SECRET);
next();
} catch (err) {
console.log(err.message);
res.status(401).json({ msg: "Error authenticating token" });
}
};
module.exports = authToken;