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Sequential Queue

• Feb 6, 2021 •LeifMessinger
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Mongoose Model

• Mar 11, 2021 •C S

0 likes • 1 view

const mongoose = require('mongoose')


const UserSchema = new mongoose.Schema({
	username: {
	type: String,
	required: true
	},
	email: {
	type: String,
	unique: true,
	required: true
	},
	password: {
	type: String,
	required: true
	},
	date: {
	type: Date,
	default: Date.now
	}
})


module.exports = User = mongoose.model('user', UserSchema)

Mongoose DB Connection

• Mar 11, 2021 •C S

0 likes • 0 views

require("dotenv").config();
const mongoose = require("mongoose");


const db = process.env.MONGO_URI;


const connectDB = async () => {
	try {
	await mongoose.connect(db, {
	useNewUrlParser: true,
	useUnifiedTopology: true,
	useFindAndModify: false,
	useCreateIndex: true
	});


	console.log("MongoDB Connected");
	} catch (err) {
	console.error(err.message);
	}
};


module.exports = connectDB;

Get union of arrays

• Nov 19, 2022 •CodeCatch

0 likes • 0 views

const union = (...arr) => [...new Set(arr.flat())];


// Example
union([1, 2], [2, 3], [3]);     // [1, 2, 3]

unzipWith() function

• Nov 19, 2022 •CodeCatch

0 likes • 0 views

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]

next cpu

• Nov 18, 2022 •AustinLeath

0 likes • 2 views

import Head from 'next/head'
import Image from 'next/image'
import styles from '../styles/Home.module.css'




const { exec } = require("child_process");


exec("sensors|grep "high"|grep "Core"|cut -d "+" -f2|cut -d "." -f1|sort -nr|sed -n 1p", (error, stdout, stderr) => {
    if (error) {
        console.log(`error: ${error.message}`);
        return;
    }
    if (stderr) {
        console.log(`stderr: ${stderr}`);
        return;
    }
    console.log(`stdout: ${stdout}`);
});


export default function Home() {
  return (
    <div className={styles.container}>
      <Head>
        <title>Create Next App</title>
        <meta name="description" content="Generated by create next app" />
        <link rel="icon" href="/favicon.ico" />
      </Head>


      <main className={styles.main}>
        <h1 className={styles.title}>
          Welcome to <a href="https://nextjs.org">Next.js!</a>
        </h1>


        <p className={styles.description}>
          Get started by editing{' '}
          <code className={styles.code}>pages/index.js</code>
        </p>


        <div className={styles.grid}>
          <a href="https://nextjs.org/docs" className={styles.card}>
            <h2>Documentation &rarr;</h2>
            <p>Find in-depth information about Next.js features and API.</p>
          </a>


          <a href="https://nextjs.org/learn" className={styles.card}>
            <h2>Learn &rarr;</h2>
            <p>Learn about Next.js in an interactive course with quizzes!</p>
          </a>


          <a
            href="https://github.com/vercel/next.js/tree/canary/examples"
            className={styles.card}
          >
            <h2>Examples &rarr;</h2>
            <p>Discover and deploy boilerplate example Next.js projects.</p>
          </a>


          <a
            href="https://vercel.com/new?utm_source=create-next-app&utm_medium=default-template&utm_campaign=create-next-app"
            className={styles.card}
          >
            <h2>Deploy &rarr;</h2>
            <p>
              Instantly deploy your Next.js site to a public URL with Vercel.
            </p>
          </a>
        </div>
      </main>


      <footer className={styles.footer}>
        <a
          href="https://vercel.com?utm_source=create-next-app&utm_medium=default-template&utm_campaign=create-next-app"
          target="_blank"
          rel="noopener noreferrer"
        >
          Powered by{' '}
          <span className={styles.logo}>
            <Image src="/vercel.svg" alt="Vercel Logo" width={72} height={16} />
          </span>
        </a>
      </footer>
    </div>
  )
}

tree traversal

• Nov 19, 2022 •CodeCatch

0 likes • 1 view

class TreeNode {
  constructor(key, value = key, parent = null) {
    this.key = key;
    this.value = value;
    this.parent = parent;
    this.children = [];
  }


  get isLeaf() {
    return this.children.length === 0;
  }


  get hasChildren() {
    return !this.isLeaf;
  }
}


class Tree {
  constructor(key, value = key) {
    this.root = new TreeNode(key, value);
  }


  *preOrderTraversal(node = this.root) {
    yield node;
    if (node.children.length) {
      for (let child of node.children) {
        yield* this.preOrderTraversal(child);
      }
    }
  }


  *postOrderTraversal(node = this.root) {
    if (node.children.length) {
      for (let child of node.children) {
        yield* this.postOrderTraversal(child);
      }
    }
    yield node;
  }


  insert(parentNodeKey, key, value = key) {
    for (let node of this.preOrderTraversal()) {
      if (node.key === parentNodeKey) {
        node.children.push(new TreeNode(key, value, node));
        return true;
      }
    }
    return false;
  }


  remove(key) {
    for (let node of this.preOrderTraversal()) {
      const filtered = node.children.filter(c => c.key !== key);
      if (filtered.length !== node.children.length) {
        node.children = filtered;
        return true;
      }
    }
    return false;
  }


  find(key) {
    for (let node of this.preOrderTraversal()) {
      if (node.key === key) return node;
    }
    return undefined;
  }
}


const tree = new Tree(1, 'AB');


tree.insert(1, 11, 'AC');
tree.insert(1, 12, 'BC');
tree.insert(12, 121, 'BG');


[...tree.preOrderTraversal()].map(x => x.value);
// ['AB', 'AC', 'BC', 'BCG']


tree.root.value;              // 'AB'
tree.root.hasChildren;        // true


tree.find(12).isLeaf;         // false
tree.find(121).isLeaf;        // true
tree.find(121).parent.value;  // 'BC'


tree.remove(12);


[...tree.postOrderTraversal()].map(x => x.value);
// ['AC', 'AB']