const regex = /\D+/gm;

const str =`01. Dil Jalta Hai To Jalne De Film: Pehli Nazar Artiste: Mukesh 02. Gaaye Ja Geet Milan Ke Film: Mela Artiste: Mukesh 03. Zinda Hoon Is Tarah Film: Aag Artiste: Mukesh 04. Chhod Gaye Balam Mujhe Film: Barsaat Artistes: Lata Mangeshkar,Mukesh 05. Patli Kamar Hai Film: Barsaat Artistes: Lata Mangeshkar,Mukesh 06. Tu Kahe Agar Film: Andaz Artiste: Mukesh 07. Jhoom Jhoom Ke Nacho Aaj Film: Andaz Artiste: Mukesh 08. Teri Duniya Mein Dil Lagta Nahin Film: Bawre Nain Artiste: Mukesh 09. Khayalon Mein Kisi Ke Is Tarah Film: Bawre Nain Artistes: Mukesh,Geeta Dutt 10. Awara Hoon Film: Awaara Artiste: Mukesh 11. Dam Bhar Jo Udhar Munh Phere Film: Awaara Artistes: Lata Mangeshkar,Mukesh 12. Bade Armanon Se Film: Malhar Artistes: Lata Mangeshkar,Mukesh 13. Hanste Bhi Rahe Rote Bhi Film: Awaara Artiste: Mukesh 14. Hum Tujhse Mohabbat Karke Sanam Film: Awaara Artiste: Mukesh 15. Ae Dil Na Mujhse Chhupa Film: Badal Artistes: Lata Mangeshkar,Mukesh 16. Aa Ja Re Ab Mera Dil Pukare Film: Aah Artistes: Mukesh,Lata Mangeshkar 17. Chhoti Si Yeh Zindagani Film: Aah Artiste: Mukesh 18. Mera Joota Hai Japani Film: Shree 420 Artiste: Mukesh 19. Ramaiya Vastavaiya Film: Shree 420 Artistes: Lata Mangeshkar, Mohammed Rafi,Mukesh 20. Ichak Dana Beechak Dana Film: Shree 420 Artistes: Lata Mangeshkar,Mukesh 21. Zindagi Khwab Hai Film: Jagte Raho Artiste: Mukesh 22. Suhana Safar Aur Yeh Mausam Film: Madhumati Artiste: Mukesh 23. Chin-O-Arab Hamara Hindustan Film: Phir Subah Hogi Artiste: Mukesh 24. Yeh Mera Diwanapan Hai Film: Yahudi Artiste: Mukesh 25. Dil Tadap Tadap Ke Kah Raha Film: Madhumati Artistes: Mukesh,Lata Mangeshkar 26. Aansoo Bhari Hai Ye Jeevan Ki Film: Parvarish Artiste: Mukesh 27. Jis Pyar Mein Yeh Haal Ho Film: Phir Subah Hogi Artistes: Mukesh,Mohammed Rafi 28. Phir Na Kije Meri Gustakh Film: Phir Subah Hogi Artistes: Mukesh,Asha Bhosle 29. Woh Subah Kabhi To Aayegi Film: Phir Subah Hogi Artistes: Mukesh,Asha Bhosle 30. Woh Subah Kabhi To Aayegi Film: Phir Subah Hogi Artiste: Mukesh 31. Kisi Ki Muskurahaton Se Film: Anari Artiste: Mukesh 32. Woh Chand Khila Woh Tare Film: Anari Artistes: Lata Mangeshkar,Mukesh 33. Dil Ki Nazar Se Film: Anari Artistes: Lata Mangeshkar,Mukesh 34. Sab Kuchh Seekha Ham Ne Film: Anari Artiste: Mukesh 35. Ruk Ja O Janewali Ruk Ja Film: Kanhaiya Artiste: Mukesh 36. Yaad Aai Aadhi Raat Ko Film: Kanhaiya Artiste: Mukesh 37. Nain Dwar Se Man Men Woh Aake (part one) Film: Sawan Artistes: Lata Mangeshkar,Mukesh 38. Nain Dwar Se Man Men Woh Aake (Part two) Film: Sawan Artistes: Lata Mangeshkar,Mukesh 39. Ek Raat Men Do Do Chand Khile Film: Barkha Artistes: Mukesh,Lata Mangeshkar 40. Naina Hai Jadu Bhare Film: Bedard Zamana Kya Jane Artiste: Mukesh 41. Jaoon Kahan Bata Ae Dil Film: Chhoti Bahen Artiste: Mukesh 42. Mujhe Mere Haal Pe Chhod Do Film: Kanhaiya Artiste: Mukesh 43. Nee Baliye Rut Hai Bahar Ki Film: Kanhaiya Artistes: Lata Mangeshkar,Mukesh 44. Dil Lootnewale Jadugar Film: Madari Artistes: Lata Mangeshkar,Mukesh 45. Main Nashe Men Hoon Film: Main Nashe Mein Hoon Artiste: Mukesh 46. Duniya Walon Se Door Film: Ujala Artistes: Lata Mangeshkar,Mukesh 47. Dum Dum Diga Diga Film: Chhalia Artiste: Mukesh 48. Chhalia Mera Naam Film: Chhalia Artiste: Mukesh 49. Mere Toote Huye Dil Se Film: Chhalia Artiste: Mukesh 50. Mujhko Is Raat Ki Tanhai Mein Film: Dil Bhi Tera Hum Bhi Tere Artiste: Mukesh 51. Yeh Wada Karen Hum Film: Dil Bhi Tera Hum Bhi Tere Artistes: Lata Mangeshkar,Mukesh 52. Ankhon Mein Rang Kyon Aaya Film: Ek Phool Char Kante Artistes: Mukesh,Lata Mangeshkar 53. Matwali Naar Thumak Thumak Film: Ek Phool Char Kante Artiste: Mukesh 54. Hum Hindustani Film: Hum Hindustani Artiste: Mukesh 55. Ham Bhi Hain Tum Bhi Ho Film: Jis Desh Mein Ganga Behti Hai Artistes: Lata Mangeshkar,Geeta Dutt, Mukesh,Manna Dey,Mahendra Kapoor 56. Honthon Pe Sachai Film: Jis Desh Mein Ganga Behti Hai Artiste: Mukesh 57. Aa Ab Laut Chalen Film: Jis Desh Mein Ganga Behti Hai Artistes: Mukesh,Lata Mangeshkar 58. Jis Desh Men Ganga Behti Hai Film: Jis Desh Mein Ganga Behti Hai Artiste: Mukesh 59. Begani Shadi Men Abdulla Diwana Film: Jis Desh Mein Ganga Behti Hai Artistes: Mukesh,Lata Mangeshkar 60. Mera Naam Raju Film: Jis Desh Mein Ganga Behti Hai Artiste: Mukesh 61. Haan Diwana Hoon Main Film: Saranga Artiste: Mukesh 62. Saranga Teri Yaad Mein Film: Saranga Artiste: Mukesh 63. Pyar Kar Le Film: Jis Desh Mein Ganga Behti Hai Artiste: Mukesh 64. Yeh Mausam Rangeen Sama Film: Modern Girl Artistes: Suman Kalyanpur,Mukesh 65. Haseen Ho Khuda To Nahin Ho Film: Mud Mud Ke Na Dekh Artiste: Mukesh 66. Nain Tumhare Mazedar Film: Junglee Artistes: Asha Bhosle,Mukesh 67. Bikhra Ke Zulfen Chaman Mein Film: Nazrana Artistes: Lata Mangeshkar,Mukesh 68. Dekho Mausam Kya Bahar Hai Film: Opera House Artistes: Lata Mangeshkar,Mukesh 69. Wafa Jin Se Ki Bewafa Ho Gaye Film: Pyaar Ka Saagar Artiste: Mukesh 70. Gardish Men Ho Tare Film: Reshmi Roomal Artiste: Mukesh 71. Ek Manzil Rahi Do Film: Sanjog Artistes: Lata Mangeshkar,Mukesh 72. Jana Tumhare Pyar Mein Film: Sasural Artiste: Mukesh 73. Mehlon Ne Chheen Liya Bachpan Film: Zabak Artistes: Lata Mangeshkar,Mukesh 74. Tum Roothi Raho Film: Aas Ka Panchhi Artistes: Lata Mangeshkar,Mukesh 75. Gaa Diwane Jhoom Ke Film: Flat No. 9 Artiste: Mukesh 76. Apni Ulfat Pe Zamane Ka Film: Sasural Artistes: Lata Mangeshkar,Mukesh 77. Tel Malish Boot Polish Film: Tel Malish Boot Polish Artiste: Mukesh 78. Ae Dil-E-Awara Chal Film: Dr. Vidya Artiste: Mukesh 79. Lakhon Tare Aasman Per Film: Hariyali Aur Rasta Artistes: Lata Mangeshkar,Mukesh 80. Allah Jane Kya Hoga Aage Film: Hariyali Aur Rasta Artistes: Lata Mangeshkar,Mukesh 81. Bol Meri Taqdeer Men Kya Hai Film: Hariyali Aur Rasta Artistes: Lata Mangeshkar,Mukesh 82. Teri Yaad Dilse Bhulane Chala Hoon Film: Hariyali Aur Rasta Artiste: Mukesh 83. Jhumti Chali Hawa Film: Sangeet Samrat Tansen Artiste: Mukesh 84. Main Aashiq Hoon Baharon Ka Film: Aashiq Artiste: Mukesh 85. O Janewale Ho Sake To Laut Ke Aana Film: Bandini Artiste: Mukesh 86. Socha Tha Pyar Ham Na Karenge Film: Bluff Master Artiste: Mukesh 87. Tum Agar Mujhko Na Chaho To Film: Dil Hi To Hai Artiste: Mukesh 88. Chura Le Na Tumko Ye Mausam Suhana Film: Dil Hi To Hai Artistes: Suman Kalyanpur,Mukesh 89. Sunoji Suno Hamari Bhi Suno Film: Ek Dil Sau Afsane Artiste: Mukesh 90. Yeh Kisne Geet Chheda Film: Meri Surat Teri Ankhen Artistes: Suman Kalyanpur,Mukesh 91. Chori Chori Jo Tumse Mile Film: Parasmani Artistes: Lata Mangeshkar,Mukesh 92. Chand Aahen Bharega Film: Phool Bane Angare Artiste: Mukesh 93. Jab Gham-E-Ishq Satata Hai Film: Kinare Kinare Artiste: Mukesh 94. Hamne Tujhko Pyar Kiya Hai Film: Dulha Dulhan Artiste: Mukesh 95. Jo Pyar Tune Mujhko Diya Tha Film: Dulha Dulhan Artiste: Mukesh 96. O Mehbooba Film: Sangam Artiste: Mukesh 97. Bol Radha Bol Film: Sangam Artistes: Mukesh,Vyjayanthimala 98. Dost Dost Na Raha Pyar Pyar Na Raha Film: Sangam Artiste: Mukesh 99. Har Dil Jo Pyar Karega Film: Sangam Artistes: Lata Mangeshkar,Mukesh, Mahendra Kapoor 100. Chal Mere Dil Lahrake Chal Film: Ishaara Artiste: Mukesh 101. Ham Chhod Chale Hain Mehfil Ko Film: Ji Chahta Hai Artiste: Mukesh 102. Chamke Chand Poonam Ka Film: Mahasati Behula Artistes: Suman Kalyanpur,Mukesh 103. Jot Se Jot Jagake Chalo (Male) Film: Sant Gyaneshwar Artiste: Mukesh 104. Teri Nigahon Pe Mar Mar Gaye Ham Film: Shabnam Artiste: Mukesh 105. Chand Si Mehbooba Ho Meri Film: Himalay Ki God Mein Artiste: Mukesh 106. Main To Ek Khwab Hoon Film: Himalay Ki God Mein Artiste: Mukesh 107. Humsafar Mere Humsafar Film: Purnima Artistes: Lata Mangeshkar,Mukesh 108. Jis Dil Mein Basa Tha Pyar Tera Film: Saheli Artiste: Mukesh MUKESH 109. Mera Rang De Basanti Chola Film: Shaheed Artistes: Mukesh,Rajendra Mehta, Mahendra Kapoor 110. Dil Ne Phir Yaad Kiya Film: Dil Ne Phir Yaad Kiya Artistes: Mohammed Rafi,Suman Kalyanpur,Mukesh 111. Raat Aur Din Diya Jale Film: Raat Aur Din Artiste: Mukesh 112. Sajan Re Jhoot Mat Bolo Film: Teesri Kasam Artiste: Mukesh 113. Sajanwa Bairi Ho Gayi Hamar Film: Teesri Kasam Artiste: Mukesh 114. Duniya Bananewale Film: Teesri Kasam Artiste: Mukesh 115. Aaya Hai Mujhe Phir Yaad Film: Devar Artiste: Mukesh 116. Tum Bin Jeevan Kaise Beeta Film: Anita Artiste: Mukesh 117. Chale Jana Zara Thahro (Duet) Film: Around The World Artistes: Mukesh,Sharada 118. Duniya Ki Sair Kar Lo Film: Around The World Artistes: Mukesh,Sharada 119. Yeh Kaun Chitrakar Hai Film: Boond Jo Ban Gayi Moti Artiste: Mukesh 120. Waqt Karta Jo Wafa Aap Hamare Hote Film: Dil Ne Pukara Artiste: Mukesh 121. Hum To Tere Aashiq Hain Film: Farz Artistes: Lata Mangeshkar,Mukesh 122. Sawan Ka Mahina Film: Milan Artistes: Lata Mangeshkar,Mukesh 123. Main To Diwana Film: Milan Artiste: Mukesh 124. Hum Tum Yug Yug Se (Part one) Film: Milan Artistes: Lata Mangeshkar,Mukesh 125. Bol Gori Bol Tera Kaun Piya Film: Milan Artistes: Lata Mangeshkar,Mukesh 126. Mehboob Mere Mehboob Mere Film: Patthar Ke Sanam Artistes: Lata Mangeshkar,Mukesh 127. Tauba Yeh Matwali Chaal Film: Patthar Ke Sanam Artiste: Mukesh 128. Gore Gore Chand Se Mukh Pe Film: Anita Artiste: Mukesh 129. Joshe Jawani Hai Re Hai Film: Around The World Artiste: Mukesh 130. Haan Maine Bhi Pyar Kiya Film: Boond Jo Ban Gayi Moti Artistes: Mukesh,Suman Kalyanpur 131. Ham To Jate Apne Gaon Film: Diwana Artiste: Mukesh 132. Ram Kare Aisa Ho Jaye Film: Milan Artiste: Mukesh 133. Chandan Sa Badan Chanchal Chitwan (Male) Film: Saraswatichandra Artiste: Mukesh 134. Hamne Apna Sab Kuchh Khoya Film: Saraswatichandra Artiste: Mukesh 135. Phool Tumhe Bheja Hai Khat Mein Film: Saraswatichandra Artistes: Lata Mangeshkar,Mukesh 136. Khush Raho Film: Suhaag Raat Artiste: Mukesh 137. Diwano Se Mat Poochho Film: Upkar Artiste: Mukesh 138. Mera Pyar Bhi Tu Hai Film: Saathi Artistes: Mukesh,Suman Kalyanpur 139. Oh Re Taal Mile Nadi Ke Jal Mein Film: Anokhi Raat Artiste: Mukesh 140. Dulhan Se Tumhara Milan Hoga Film: Anokhi Raat Artiste: Mukesh 141. Tumne Mujhe Dekha Film: Maa Artistes: Usha Mangeshkar,Mukesh 142. Chal Akela Chal Akela Film: Sambandh Artiste: Mukesh 143. Je Hum Tum Chori Se Film: Dharti Kahe Pukar Ke Artistes: Mukesh,Lata Mangeshkar 144. Chandi Ki Deewar Film: Vishwas Artiste: Mukesh 145. Woh Kaun Hai Film: Anjaana Artistes: Lata Mangeshkar,Mukesh 146. Zindagi Ka Ajab Fasana Hai Film: Chhoti Chhoti Baaten Artistes: Lata Mangeshkar,Mukesh 147. Khushi Ki Woh Raat Aa Gayi Film: Dharti Kahe Pukar Ke Artiste: Mukesh 148. Muskura Ke Humko Loota Aapne Film: Vishwas Artistes: Asha Bhosle,Mukesh 149. Main To Har Mod Par (Happy) Film: Chetna Artiste: Mukesh 150. Yeh Kaisa Aaya Zamana Film: Humjoli Artistes: Kishore Kumar,Mukesh,Mehmood 151. Jis Gali Mein Tera Ghar Film: Kati Patang Artiste: Mukesh 152. Jeena Yahan Marna Yahan Film: Mera Naam Joker Artiste: Mukesh 153. Daagh Na Lag Jaye Film: Mera Naam Joker Artistes: Asha Bhosle,Mukesh 154. Jane Kahan Gaye Woh Din Film: Mera Naam Joker Artiste: Mukesh 155. Kehta Hai Joker Sara Zamana Film: Mera Naam Joker Artiste: Mukesh 156. Teetar Ke Do Aage Teetar Film: Mera Naam Joker Artistes: Asha Bhosle,Simi Garewal, Mukesh 157. Kisi Raah Men Kisi Mod Par Film: Mere Humsafar Artistes: Lata Mangeshkar,Mukesh 158. Woh Tere Pyar Ka Gham Film: My Love Artiste: Mukesh 159. Gangaram Ki Samajh Men Na Aaye Film: Pehchan Artistes: Sharada,Suman Kalyanpur,Mukesh 160. Sabse Bada Naadan Film: Pehchan Artiste: Mukesh 161. Bas Yehi Apradh Main Har Baar Film: Pehchan Artiste: Mukesh 162. Aaya Na Humko Pyar Jatana Film: Pehchan Artistes: Suman Kalyanpur,Mukesh 163. Koi Jab Tumhara Hriday Tod De Film: Purab Aur Pachhim Artiste: Mukesh 164. Jo Tumko Ho Pasand Wohi Baat Karenge Film: Safar Artiste: Mukesh 165. Meri Tamannaon Ki Taqdeer Tum (Male) Film: Holi Aaee Re Artiste: Mukesh 166. Zikra Hota Hai Jab Qayamat Ka Film: My Love Artiste: Mukesh 167. Ae Meri Jaan Film: Puraskar Artistes: Asha Bhosle,Mukesh 168. Nateeja Humari Mohabbat Ka Film: Puraskar Artistes: Asha Bhosle,Mukesh 169. Jane Chale Jate Hain Kahan Film: Pushpanjali Artiste: Mukesh 170. Zindagi Hai Kya Bolo Film: Satyakam Artistes: Kishore Kumar,Mukesh, Mahendra Kapoor 171. Holi Khelat Nandlala Film: Mastana Artistes: Asha Bhosle,Mohammed Rafi,Mukesh 172. Kahin Door Jab Din Dhal Jaye Film: Anand Artiste: Mukesh 173. Maine Tere Liye Film: Anand Artiste: Mukesh 174. Zuban Pe Dard Bhari Dastan Film: Maryada Artiste: Mukesh 175. Taron Men Sajke Apne Suraj Se Film: Jal Bin Machhli Nritya Bin Bijli Artiste: Mukesh 176. Ae Meri Ankhon Ke Pahle Sapne Film: Man Mandir Artistes: Lata Mangeshkar,Mukesh 177. Haal Chaal Thik Thak Hai Film: Mere Apne Artistes: Kishore Kumar,Mukesh 178. Darpan Ko Dekha Tune Film: Upaasna Artiste: Mukesh 179. Tick Tick Tick Chalti Jaye Ghadi Film: Kal Aaj Aur Kal Artistes: Kishore Kumar,Asha Bhosle,Mukesh 180. Paani Re Paani Film: Shor Artistes: Lata Mangeshkar,Mukesh 181. Ek Pyar Ka Naghma Hai (Happy) Film: Shor Artistes: Lata Mangeshkar,Mukesh 182. Nayan Hamare Sanjh Sakare Film: Annadata Artiste: Mukesh 183. Dheere Dheere Bol Koi Sun Na Le Film: Gora Aur Kala Artistes: Mukesh,Lata Mangeshkar 184. Badi Door Se Aaye Hain Film: Samjhauta Artistes: Mohammed Rafi,Mukesh 185. Barkha Rani Zara Jamke Barso Film: Sabak Artiste: Mukesh 186. Tan Man Dhan Sab Hai Tera Film: Manchali Artiste: Mukesh 187. Kai Baar Yun Bhi Dekha Hai Film: Rajnigandha Artiste: Mukesh 188. Kahin Karti Hogi Woh Mera Intezar Film: Phir Kab Milogi Artistes: Mukesh,Lata Mangeshkar 189. Main Na Bhoolunga Film: Roti Kapada Aur Makaan Artistes: Lata Mangeshkar,Mukesh 190. Mehngai Mar Gayee Film: Roti Kapada Aur Makaan Artistes: Lata Mangeshkar,Mukesh, Jani Babu Qawal,Narendra Chanchal 191. Kya Khoob Lagti Ho Film: Dharmatma Artistes: Mukesh,Kanchan 192. Tumne Kisi Se Kabhi Pyar Kiya Hai Film: Dharmatma Artistes: Mukesh,Kanchan 193. Phool Ahista Phenko Film: Prem Kahani Artistes: Lata Mangeshkar,Mukesh 194. Chal Sanyasi Mandir Mein Film: Sanyasi Artistes: Lata Mangeshkar,Mukesh 195. Sun Baal Bramhachari Film: Sanyasi Artistes: Lata Mangeshkar,Mukesh 196. Ek Din Bik Jayega Mati Ke Mol (Happy) Film: Dharam Karam Artiste: Mukesh 197. Yeh Din Kya Aaye Film: Chhoti Si Baat Artiste: Mukesh 198. Yeh Duniya Ek Numbri Film: Dus Numbri Artiste: Mukesh 199. Mujhe Dard Rahta Hai Film: Dus Numbri Artistes: Lata Mangeshkar,Mukesh 200. Kabhi Kabhi Mere Dil Mein (Duet) Film: Kabhi Kabhie Artistes: Mukesh,Lata Mangeshkar 201. Main Pal Do Pal Ka Shair Hoon Film: Kabhi Kabhie Artiste: Mukesh 202. Na Tum Ho Yaar Aloo Film: Dus Numbri Artistes: Mukesh,Manna Dey 203. Dilruba Dilliwali Film: Dus Numbri Artistes: Asha Bhosle,Mukesh, Manna Dey 204. Chahe Aaj Mujhe Na Pasand Karo Film: Darinda Artiste: Mukesh 205. Suhani Chandni Raaten Film: Mukti Artiste: Mukesh 206. Lalla Lalla Lori Doodh Ki Katori Film: Mukti Artiste: Mukesh 207. Chanchal Sheetal Nirmal Komal Film: Satyam Shivam Sundaram Artistes: Mukesh,Zeenat Aman 208. Hum Dono Milke Kagaz Pe Dil Pe Film: Tumhari Kassam Artistes: Asha Bhosle,Mukesh`;
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let count=1;
while ((m = regex.exec(str)) !== null) {
    // This is necessary to avoid infinite loops with zero-width matches
    if (m.index === regex.lastIndex) {
        regex.lastIndex++;
    }
    
    // The result can be accessed through the `m`-variable.
    m.forEach((match, groupIndex) => {
      count=count+1;
        console.log(match.replace('.', ''));
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}

Javascript Online Compiler

Write, Run & Share Javascript code online using OneCompiler's JS online compiler for free. It's one of the robust, feature-rich online compilers for Javascript language. Getting started with the OneCompiler's Javascript editor is easy and fast. The editor shows sample boilerplate code when you choose language as Javascript and start coding.

About Javascript

Javascript(JS) is a object-oriented programming language which adhere to ECMA Script Standards. Javascript is required to design the behaviour of the web pages.

Key Features

  • Open-source
  • Just-in-time compiled language
  • Embedded along with HTML and makes web pages alive
  • Originally named as LiveScript.
  • Executable in both browser and server which has Javascript engines like V8(chrome), SpiderMonkey(Firefox) etc.

Syntax help

STDIN Example

var readline = require('readline');
var rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
  terminal: false
});

rl.on('line', function(line){
    console.log("Hello, " + line);
});

variable declaration

KeywordDescriptionScope
varVar is used to declare variables(old way of declaring variables)Function or global scope
letlet is also used to declare variables(new way)Global or block Scope
constconst is used to declare const values. Once the value is assigned, it can not be modifiedGlobal or block Scope

Backtick Strings

Interpolation

let greetings = `Hello ${name}`

Multi line Strings

const msg = `
hello
world!
`

Arrays

An array is a collection of items or values.

Syntax:

let arrayName = [value1, value2,..etc];
// or
let arrayName = new Array("value1","value2",..etc);

Example:

let mobiles = ["iPhone", "Samsung", "Pixel"];

// accessing an array
console.log(mobiles[0]);

// changing an array element
mobiles[3] = "Nokia";

Arrow functions

Arrow Functions helps developers to write code in concise way, it’s introduced in ES6.
Arrow functions can be written in multiple ways. Below are couple of ways to use arrow function but it can be written in many other ways as well.

Syntax:

() => expression

Example:

const numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
const squaresOfEvenNumbers = numbers.filter(ele => ele % 2 == 0)
                                    .map(ele => ele ** 2);
console.log(squaresOfEvenNumbers);

De-structuring

Arrays

let [firstName, lastName] = ['Foo', 'Bar']

Objects

let {firstName, lastName} = {
  firstName: 'Foo',
  lastName: 'Bar'
}

rest(...) operator

 const {
    title,
    firstName,
    lastName,
    ...rest
  } = record;

Spread(...) operator

//Object spread
const post = {
  ...options,
  type: "new"
}
//array spread
const users = [
  ...adminUsers,
  ...normalUsers
]

Functions

function greetings({ name = 'Foo' } = {}) { //Defaulting name to Foo
  console.log(`Hello ${name}!`);
}
 
greet() // Hello Foo
greet({ name: 'Bar' }) // Hi Bar

Loops

1. If:

IF is used to execute a block of code based on a condition.

Syntax

if(condition){
    // code
}

2. If-Else:

Else part is used to execute the block of code when the condition fails.

Syntax

if(condition){
    // code
} else {
    // code
}

3. Switch:

Switch is used to replace nested If-Else statements.

Syntax

switch(condition){
    case 'value1' :
        //code
        [break;]
    case 'value2' :
        //code
        [break;]
    .......
    default :
        //code
        [break;]
}

4. For

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
//code  
}

5. While

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
  // code 
}

6. Do-While

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
  // code 
} while (condition);

Classes

ES6 introduced classes along with OOPS concepts in JS. Class is similar to a function which you can think like kind of template which will get called when ever you initialize class.

Syntax:

class className {
  constructor() { ... } //Mandatory Class method
  method1() { ... }
  method2() { ... }
  ...
}

Example:

class Mobile {
  constructor(model) {
    this.name = model;
  }
}

mbl = new Mobile("iPhone");