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Simple Express Server

• Oct 15, 2022 •CodeCatch
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array shuffle

• Nov 19, 2022 •CodeCatch

0 likes • 0 views

const shuffle = ([...arr]) => {
  let m = arr.length;
  while (m) {
    const i = Math.floor(Math.random() * m--);
    [arr[m], arr[i]] = [arr[i], arr[m]];
  }
  return arr;
};


const foo = [1, 2, 3];
shuffle(foo); // [2, 3, 1], foo = [1, 2, 3]

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>
  )
}

graph example

• Nov 19, 2022 •CodeCatch

0 likes • 0 views

class Graph {
  constructor(directed = true) {
    this.directed = directed;
    this.nodes = [];
    this.edges = new Map();
  }


  addNode(key, value = key) {
    this.nodes.push({ key, value });
  }


  addEdge(a, b, weight) {
    this.edges.set(JSON.stringify([a, b]), { a, b, weight });
    if (!this.directed)
      this.edges.set(JSON.stringify([b, a]), { a: b, b: a, weight });
  }


  removeNode(key) {
    this.nodes = this.nodes.filter(n => n.key !== key);
    [...this.edges.values()].forEach(({ a, b }) => {
      if (a === key || b === key) this.edges.delete(JSON.stringify([a, b]));
    });
  }


  removeEdge(a, b) {
    this.edges.delete(JSON.stringify([a, b]));
    if (!this.directed) this.edges.delete(JSON.stringify([b, a]));
  }


  findNode(key) {
    return this.nodes.find(x => x.key === key);
  }


  hasEdge(a, b) {
    return this.edges.has(JSON.stringify([a, b]));
  }


  setEdgeWeight(a, b, weight) {
    this.edges.set(JSON.stringify([a, b]), { a, b, weight });
    if (!this.directed)
      this.edges.set(JSON.stringify([b, a]), { a: b, b: a, weight });
  }


  getEdgeWeight(a, b) {
    return this.edges.get(JSON.stringify([a, b])).weight;
  }


  adjacent(key) {
    return [...this.edges.values()].reduce((acc, { a, b }) => {
      if (a === key) acc.push(b);
      return acc;
    }, []);
  }


  indegree(key) {
    return [...this.edges.values()].reduce((acc, { a, b }) => {
      if (b === key) acc++;
      return acc;
    }, 0);
  }


  outdegree(key) {
    return [...this.edges.values()].reduce((acc, { a, b }) => {
      if (a === key) acc++;
      return acc;
    }, 0);
  }
}




const g = new Graph();


g.addNode('a');
g.addNode('b');
g.addNode('c');
g.addNode('d');


g.addEdge('a', 'c');
g.addEdge('b', 'c');
g.addEdge('c', 'b');
g.addEdge('d', 'a');


g.nodes.map(x => x.value);  // ['a', 'b', 'c', 'd']
[...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);
// ['a => c', 'b => c', 'c => b', 'd => a']


g.adjacent('c');            // ['b']


g.indegree('c');            // 2
g.outdegree('c');           // 1


g.hasEdge('d', 'a');        // true
g.hasEdge('a', 'd');        // false


g.removeEdge('c', 'b');


[...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);
// ['a => c', 'b => c', 'd => a']


g.removeNode('c');


g.nodes.map(x => x.value);  // ['a', 'b', 'd']
[...g.edges.values()].map(({ a, b }) => `${a} => ${b}`);
// ['d => a']


g.setEdgeWeight('d', 'a', 5);
g.getEdgeWeight('d', 'a');  // 5

Temperature Converter

• Nov 19, 2022 •CodeCatch

0 likes • 1 view

const celsiusToFahrenheit = (celsius) => celsius * 9/5 + 32;
const fahrenheitToCelsius = (fahrenheit) => (fahrenheit - 32) * 5/9;
// Examples
celsiusToFahrenheit(15);    // 59
celsiusToFahrenheit(0);     // 32
celsiusToFahrenheit(-20);   // -4
fahrenheitToCelsius(59);    // 15
fahrenheitToCelsius(32);    // 0

arithmetic progression

• Nov 19, 2022 •CodeCatch

0 likes • 0 views

const arithmeticProgression  = (n, lim) =>
  Array.from({ length: Math.ceil(lim / n) }, (_, i) => (i + 1) * n );
  
arithmeticProgression(5, 25); // [5, 10, 15, 20, 25]

Reverse a string in Java

• Nov 20, 2022 •Helper

0 likes • 1 view

new StringBuilder(hi).reverse().toString()