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Invert Binary Tree

• Oct 15, 2022 •CodeCatch
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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>
  )
}

power set

• Nov 19, 2022 •CodeCatch

0 likes • 2 views

const powerset = arr =>
  arr.reduce((a, v) => a.concat(a.map(r => r.concat(v))), [[]]);
  
powerset([1, 2]); // [[], [1], [2], [1, 2]]

Monotonic Array

• Nov 19, 2022 •CodeCatch

0 likes • 4 views

// Time Complexity : O(N)
// Space Complexity : O(1)
 
var isMonotonic = function(nums) {
    let isMono = null;
    for(let i = 1; i < nums.length; i++) {
        if(isMono === null) {
            if(nums[i - 1] < nums[i]) isMono = 0;
            else if(nums[i - 1] > nums[i]) isMono = 1;
            continue;
        }
        if(nums[i - 1] < nums[i] && isMono !== 0) {
            return false;
        }
        else if(nums[i - 1] > nums[i] && isMono !== 1) {
            return false;
        }
    }
    
    return true;
    
};


let nums1 = [1,2,2,3]
let nums2 = [6,5,4,4]
let nums3 = [1,3,2]


console.log(isMonotonic(nums1));
console.log(isMonotonic(nums2));
console.log(isMonotonic(nums3));

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']

geometric progression

• Nov 19, 2022 •CodeCatch

0 likes • 0 views

const geometricProgression = (end, start = 1, step = 2) =>
  Array.from({
    length: Math.floor(Math.log(end / start) / Math.log(step)) + 1,
  }).map((_, i) => start * step ** i);
  
geometricProgression(256); // [1, 2, 4, 8, 16, 32, 64, 128, 256]
geometricProgression(256, 3); // [3, 6, 12, 24, 48, 96, 192]
geometricProgression(256, 1, 4); // [1, 4, 16, 64, 256]

Extracting components

• Nov 19, 2022 •CodeCatch

0 likes • 2 views

function formatDate(date) {
  return date.toLocaleDateString();
}


function Comment(props) {
  return (
    <div className="Comment">
      <div className="UserInfo">
        <img
          className="Avatar"
          src={props.author.avatarUrl}
          alt={props.author.name}
        />
        <div className="UserInfo-name">
          {props.author.name}
        </div>
      </div>
      <div className="Comment-text">{props.text}</div>
      <div className="Comment-date">
        {formatDate(props.date)}
      </div>
    </div>
  );
}


const comment = {
  date: new Date(),
  text: 'I hope you enjoy learning React!',
  author: {
    name: 'Hello Kitty',
    avatarUrl: 'https://placekitten.com/g/64/64',
  },
};
ReactDOM.render(
  <Comment
    date={comment.date}
    text={comment.text}
    author={comment.author}
  />,
  document.getElementById('root')
);