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Subsets of an array

Nov 19, 2022CodeCatch
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bucket sort

Nov 19, 2022CodeCatch

0 likes • 0 views

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]

React - Lifting State

Jan 25, 2023C S

1 like • 12 views

export const Main = () => {
const [title, setTitle] = useState('');
return (
<ChildComponent
title={title}
onChange={e => setTitle(e.target.value)}
/>
);
};
export const ChildComponent = ({ title, onChange }) => {
return (
<Box component="form" onSubmit={() => {}} noValidate mt={5}>
<TextField
fullWidth
id="title"
label="Title"
name="title"
autoComplete="title"
autoFocus
color="primary"
variant="filled"
InputLabelProps={{ shrink: true }}
value={title}
onChange={onChange}
/>
</Box>
);
};

Authenticate Discord User

Mar 28, 2023Helper

0 likes • 1 view

const Discord = require('discord.js');
const client = new Discord.Client();
const token = 'YOUR_BOT_TOKEN';
// When the bot is ready, log a message to the console
client.on('ready', () => {
console.log(`Logged in as ${client.user.tag}!`);
});
// When a user sends a message, check if they are authenticated
client.on('message', async (msg) => {
if (!msg.author.bot && !msg.author.authenticated) {
const filter = (m) => m.author.id === msg.author.id;
const collector = msg.channel.createMessageCollector(filter, { time: 15000 });
// Send an authentication message to the user
msg.author.send('Please authenticate yourself by clicking this link: ' + generateAuthURL(msg.author.id));
collector.on('collect', async (m) => {
// Check if the message contains the authentication code
if (m.content.startsWith('!auth ')) {
const code = m.content.slice(6);
const { access_token } = await getAccessToken(code);
// Set the user's authenticated status and access token
msg.author.authenticated = true;
msg.author.access_token = access_token;
collector.stop();
}
});
collector.on('end', () => {
if (!msg.author.authenticated) {
msg.author.send('Authentication timed out.');
}
});
}
});
// Generate an authentication URL for the user
function generateAuthURL(userId) {
const redirectURI = encodeURIComponent('YOUR_REDIRECT_URL');
const scopes = 'identify';
const clientID = 'YOUR_CLIENT_ID';
return `https://discord.com/api/oauth2/authorize?client_id=${clientID}&redirect_uri=${redirectURI}&response_type=code&scope=${scopes}&state=${userId}`;
}
// Exchange the authorization code for an access token
async function getAccessToken(code) {
const redirectURI = encodeURIComponent('YOUR_REDIRECT_URL');
const clientID = 'YOUR_CLIENT_ID';
const clientSecret = 'YOUR_CLIENT_SECRET';
const res = await fetch('https://discord.com/api/oauth2/token', {
method: 'POST',
headers: {
'Content-Type': 'application/x-www-form-urlencoded',
},
body: `grant_type=authorization_code&code=${code}&redirect_uri=${redirectURI}&client_id=${clientID}&client_secret=${clientSecret}`,
});
return await res.json();
}
client.login(token);

luhnCheck implementation

Nov 19, 2022CodeCatch

0 likes • 2 views

const luhnCheck = num => {
let arr = (num + '')
.split('')
.reverse()
.map(x => parseInt(x));
let lastDigit = arr.splice(0, 1)[0];
let sum = arr.reduce(
(acc, val, i) => (i % 2 !== 0 ? acc + val : acc + ((val *= 2) > 9 ? val - 9 : val)),
0
);
sum += lastDigit;
return sum % 10 === 0;
};
luhnCheck('4485275742308327'); // true
luhnCheck(6011329933655299); // true
luhnCheck(123456789); // false

linear search

Nov 19, 2022CodeCatch

0 likes • 3 views

const linearSearch = (arr, item) => {
for (const i in arr) {
if (arr[i] === item) return +i;
}
return -1;
};
linearSearch([2, 9, 9], 9); // 1
linearSearch([2, 9, 9], 7); // -1

kNearestNeighbors

Nov 19, 2022CodeCatch

0 likes • 6 views

const kNearestNeighbors = (data, labels, point, k = 3) => {
const kNearest = data
.map((el, i) => ({
dist: Math.hypot(...Object.keys(el).map(key => point[key] - el[key])),
label: labels[i]
}))
.sort((a, b) => a.dist - b.dist)
.slice(0, k);
return kNearest.reduce(
(acc, { label }, i) => {
acc.classCounts[label] =
Object.keys(acc.classCounts).indexOf(label) !== -1
? acc.classCounts[label] + 1
: 1;
if (acc.classCounts[label] > acc.topClassCount) {
acc.topClassCount = acc.classCounts[label];
acc.topClass = label;
}
return acc;
},
{
classCounts: {},
topClass: kNearest[0].label,
topClassCount: 0
}
).topClass;
};
const data = [[0, 0], [0, 1], [1, 3], [2, 0]];
const labels = [0, 1, 1, 0];
kNearestNeighbors(data, labels, [1, 2], 2); // 1
kNearestNeighbors(data, labels, [1, 0], 2); // 0