const copyToClipboard = str => {
  const el = document.createElement('textarea');
  el.value = str;
  el.setAttribute('readonly', '');
  el.style.position = 'absolute';
  el.style.left = '-9999px';
  document.body.appendChild(el);
  const selected =
    document.getSelection().rangeCount > 0
      ? document.getSelection().getRangeAt(0)
      : false;
  el.select();
  document.execCommand('copy');
  document.body.removeChild(el);
  if (selected) {
    document.getSelection().removeAllRanges();
    document.getSelection().addRange(selected);
  }
};

copyToClipboard('Lorem ipsum'); // 'Lorem ipsum' copied to clipboard.

const MongoClient = require('mongodb').MongoClient;
const assert = require('assert');

// Connection URL
const url = 'mongodb://localhost:27017';

// Database Name
const dbName = 'myproject';

// Use connect method to connect to the server
MongoClient.connect(url, function(err, client) {
  assert.equal(null, err);
  console.log("Connected successfully to server");

  const db = client.db(dbName);

  client.close();
});

function printHeap(heap, index, level) {
    if (index >= heap.length) {
        return;
    }
    console.log("  ".repeat(level) + heap[index]);
    printHeap(heap, 2 * index + 1, level + 1);
    printHeap(heap, 2 * index + 2, level + 1);
}

//You can call this function by passing in the heap array and the index of the root node, which is typically 0, and level = 0.

let heap = [3, 8, 7, 15, 17, 30, 35, 2, 4, 5, 9];
printHeap(heap,0,0)

const reverse = str => str.split('').reverse().join('');
reverse('hello world');     
// Result: 'dlrow olleh'

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

import React, { useState, useEffect } from 'react';
import Link from 'next/link';

export default function CookieBanner() {
    // Initialize with a default value (false if not previously set in localStorage)
  const [cookieConsent, setCookieConsent] = useState(() =>
    localStorage.getItem('cookieConsent') === 'true' ? true : false
  );

  useEffect(() => {
    const newCookieConsent = cookieConsent ? 'granted' : 'denied';

    window.gtag('consent', 'update', {
      analytics_storage: newCookieConsent
    });

    localStorage.setItem('cookieConsent', String(cookieConsent));
  }, [cookieConsent]);

  return !cookieConsent && (
    <div>
    <div>
        <p>
        We use cookies to enhance the user experience.{' '}
        <Link href='/privacy/'>View privacy policy</Link>
        </p>
    </div>
    <div>
        <button type="button" onClick={() => setCookieConsent(false)}>Decline</button>
        <button type="button" onClick={() => setCookieConsent(true)}>Allow</button>
    </div>
    </div>
  )
}