umair-khanzada

// Note: The time complexity of this solution is O(n)
function getMaxConsecutiveChar(str) {
  let char = preChar = str[0];
  let occurrence = count = 1;
  for(let i = 1; i < str.length; i++){
    if(preChar === str[i]) count++;
    if(count > occurrence) {
      occurrence = count;
      char = preChar;
    }

umair-khanzada

function capitalizeString(str = "") {
  // Break name into word's chunk.
  let words = str.split(' ');
  // Removed empty string, null, undefined, etc.
  let filteredWords = words.filter(word => word);
  // Capatilize words.
  let capatilizeWords = filteredWords.map(word => `${word[0].toUpperCase()}${word.slice(1)}`);
  // Concatenate words.
  return capatilizeWords.join(' ');
}

umair-khanzada

 function persistence(num, count = 0){
  return num > 9 ? persistence(eval(`${num}`.split('').join('*')), count+1) : count; 
}
 
 persistence(39) === 3 // because 3*9 = 27, 2*7 = 14, 1*4=4
                       // and 4 has only one digit

 persistence(999) === 4 // because 9*9*9 = 729, 7*2*9 = 126,
                        // 1*2*6 = 12, and finally 1*2 = 2

umair-khanzada

import axios from 'axios';

const API_CLIENT = axios.create({
  baseURL: 'base_url/api/v1/'
});

// request interceptor
const REQUEST_INTERCEPTOR = API_CLIENT.interceptors.request.use(function (config) {
  // TODO: uncomment Authorization header when token is available.
  // config.headers['Authorization'] = `Bearer ${localStorage.getItem('access_token')}`;

umair-khanzada

sudo nohup npm start &

umair-khanzada

function climbingLeaderboard(scores, alice) {
    const uniqueScores = [...new Set(scores)]; //for removing duplicate entries.
    let preIndex = uniqueScores.length,        //starting position of nested loop.
        rank = uniqueScores.length + 1,        //last rank default.
        aliceRanks = [];

    for(let i = 0; i < alice.length; i++){
      let s = preIndex;
      for(s; s--;){
        if(alice[i] < uniqueScores[s]){

umair-khanzada

<link href='https://fonts.googleapis.com/css?family=Lato:100,300,400,700,900' rel='stylesheet' type='text/css'>
<style>
    * {
        margin: 0;
        padding: 0;
        font-family: Lato;
    }
    body {
        padding: 50px 0;
        /*background: #e5e2e6;*/

umair-khanzada

function palindrome(str) {
  str = str.toLowerCase(); //convert to lowercase
  let count = Math.ceil(str.length / 2), //limit for itration
      flag = true; //palindrome or not

  for(var i = 0; i < count; i++){
      //checking 0 and the last index are same or not 
      //if not same break
      if(!(str[i] === str[str.length - i - 1])){
          flag = false;

umair-khanzada

Blockchain (A distributed ledger organized in block)
ethereum (A blockchain application platform)
EVM (EVM is the runtime environment for smart contracts)
solidity (Solidity is contract-oriented, high-level programming language for writing smart contracts which run on Ethereum Virtual Machine.)
smartcontract (A smart contract is a computer protocol intended to digitally facilitate, verify, or enforce the negotiation or performance of a contract.)
remix (Web browser based IDE that allows you to write Solidity smart contracts)
web3.js (Ethereum JavaScript API)
DApps (distributed app)
metamask (MetaMask is a bridge that allows you to visit the distributed app in your browser.
          It allows you to run Ethereum dApps right in your browser without running a full Ethereum node.)

umair-khanzada

db.getCollection('your collection').aggregate([
  {
    "$project": {
      chapters: "$books.chapters", _id: "$_id"
    }
  },
  {
    "$unwind": "$chapters"
  },
  {