Front-End coding problems including algorithms and JavaScript ones.

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153. uglify CSS class names JavaScript
152. Find Top k Elements JavaScript Algorithm
151. implement Array.prototype.map()JavaScript
150. Virtual DOM V - JSX 2 JavaScript
149. interpolation JavaScript
148. create a counter object JavaScript
147. Pick up stones JavaScript
146. implement Array.prototype.reduce()JavaScript
145. most frequently occurring character JavaScript
144. serialize and deserialize data types not supported in JSON JavaScript
143. Virtual DOM IV - JSX 1 JavaScript
142. lit-html 1 - tagged templates JavaScript lit-html
141. implement btoa()JavaScript
140. Virtual DOM III - Functional Component JavaScript
139. implement _.partial()JavaScript Lodash
138. Intersection of two sorted arrays JavaScript Algorithm
137. binary tree vertical traversal JavaScript Algorithm
136. find median of two sorted array JavaScript Algorithm
135. localStorage with expiration JavaScript
134. create your own Cookie JavaScript
133. roman numerals to integer JavaScript
132. the angle between hour hand and minute hand of a clock JavaScript U-NEXT
131. implement _.chunk()JavaScript Lodash
130. create LazyMan()JavaScript
129. BigDecimal Division JavaScript Algorithm
128. BigDecimal multiplication JavaScript Algorithm
127. BigDecimal subtraction JavaScript Algorithm
126. BigDecimal addition JavaScript Algorithm
125. implement classNames()JavaScript
124. calculate arithmetic expression JavaScript Algorithm
123. implement Promise.prototype.finally()JavaScript
122. implement memoizeOne()JavaScript
121. A number sequence JavaScript
120. create `isPrime()`JavaScript Algorithm
119. create a tokenizer JavaScript
118. Virtual DOM II - createElement JavaScript
117. event delegation JavaScript
116. implement Object.is()JavaScript
115. implement BigInt division JavaScript
114. implement BigInt multiplication JavaScript
113. Virtual DOM I JavaScript Algorithm DOM
112. remove duplicate characters in a string JavaScript Algorithm
111. Count palindromic substrings JavaScript Algorithm
110. serialize and deserialize binary tree JavaScript Algorithm
109. implement `Math.pow()`JavaScript Algorithm
108. Implement a Stack by using Queue JavaScript Algorithm
107. Find the largest difference JavaScript Algorithm
106. Find two numbers that sum up to 0 JavaScript Algorithm
105. find the first duplicate character in a string JavaScript Apple
104. Traverse DOM level by level JavaScript Algorithm DOM
103. implement Math.sqrt()JavaScript Algorithm
102. validate string of parentheses JavaScript Algorithm
101. merge identical API calls JavaScript
100. detect circle in linked list JavaScript Algorithm
99. extract all anchor element from HTML string JavaScript
98. validate an IP address JavaScript
97. compress a string JavaScript
96. count "1" in binary form JavaScript
95. implement String.prototype.trim()JavaScript
94. implement your own `Object.create`JavaScript
93. Generate Fibonacci Number with recursion JavaScript
92. throttle Promises JavaScript
91. invert a binary tree JavaScript Algorithm
90. write your own `instanceof`JavaScript
89. Next Right Sibling JavaScript DOM Microsoft
88. support negative Array index in JavaScript JavaScript
87. longest substring with unique characters JavaScript Algorithm
86. Generate Fibonacci Number JavaScript Algorithm
85. implement `_.get()`JavaScript Lodash
84. create a fake timer (setInterval)JavaScript
83. create an interval JavaScript ByteDance
82. find available meeting slots JavaScript Algorithm Airbnb
81. merge sorted arrays JavaScript Algorithm ByteDance
80. implement your own URLSearchParams JavaScript
79. convert snake_case to camelCase JavaScript
78. convert HEX color to RGBA JavaScript
77. implement BigInt subtraction with sign JavaScript
76. implement BigInt addition with sign JavaScript
75. implement BigInt subtraction JavaScript Algorithm
74. implement Observable Transformation Operators JavaScript
73. implement Observable fromEvent()JavaScript
72. implement Observable interval()JavaScript
71. implement Observable Subject JavaScript
70. implement Observable.from()JavaScript
69. implement deep equal `_.isEqual()`JavaScript Lodash
68. get DOM tags JavaScript Algorithm DOM
67. create your own Promise JavaScript Airbnb
66. remove duplicates from an array JavaScript Algorithm
65. add comma to number JavaScript
64. auto-retry Promise on rejection JavaScript
63. create `_.cloneDeep()`JavaScript Algorithm Lodash
62. implement BigInt addition JavaScript Algorithm
61. create your own `Function.prototype.call`JavaScript
60. create your own `new` operator JavaScript
59. create a browser history JavaScript
58. get DOM tree height JavaScript Algorithm DOM
57. create an Observable JavaScript
56. call APIs with pagination JavaScript
55. highlight keywords in HTML string JavaScript Algorithm
54. flatten Thunk JavaScript
53. write your own `extends` in es5 JavaScript
52. create a middleware system JavaScript
51. search element right after target with Binary Search(possible duplicate array)JavaScript Algorithm
50. search element right before target with Binary Search(possible duplicate array)JavaScript Algorithm
49. search last index with Binary Search(possible duplicate array)JavaScript Algorithm
48. search first index with Binary Search(possible duplicate array)JavaScript Algorithm
47. reverse a linked list JavaScript Algorithm
46. implement `_.once()`JavaScript Lodash
45. find the K-th largest element in an unsorted array JavaScript Algorithm
44. implement Selection Sort JavaScript Algorithm
43. implement Quick Sort JavaScript Algorithm
42. implement Insertion Sort JavaScript Algorithm
41. implement Merge Sort JavaScript Algorithm
40. implement Bubble Sort JavaScript Algorithm
39. implement range()JavaScript
38. implement `jest.spyOn()`JavaScript
37. implement Binary Search (unique)JavaScript
36. create a fake timer(setTimeout)JavaScript
35. implement `Promise.race()`JavaScript
34. implement `Promise.any()`JavaScript
33. implement `Promise.allSettled()`JavaScript
32. implement `Promise.all()`JavaScript
31. implement async helper - `race()`JavaScript
30. implement async helper - `parallel()`JavaScript
29. implement async helper - `sequence()`JavaScript
28. implement clearAllTimeout()JavaScript
27. implement completeAssign() JavaScript
26. implement Object.assign()JavaScript
25. Reorder array with new indexes JavaScript Algorithm
24. create a Priority Queue in JavaScript JavaScript Algorithm
23. create a sum()JavaScript
22. implement JSON.parse()JavaScript
21. implement JSON.stringify()JavaScript
20. Detect data type in JavaScript JavaScript
19. find corresponding node in two identical DOM tree JavaScript
18. Improve a function JavaScript
17. Create a simple store for DOM element JavaScript
16. create an Event Emitter JavaScript
15. implement a simple DOM wrapper to support method chaining like jQuery JavaScript
14. Implement a general memoization function - `memo()`JavaScript
13. Implement a Queue by using Stack JavaScript Algorithm ByteDance
12. implement Immutability helper JavaScript
11. what is Composition? create a pipe()JavaScript
10. first bad version JavaScript Algorithm
9. decode message JavaScript
8. can you shuffle() an array?JavaScript
7. implement debounce() with leading & trailing option JavaScript Lodash
6. implement basic debounce()JavaScript Lodash
5. implement throttle() with leading & trailing option JavaScript Lodash
4. implement basic throttle()JavaScript Lodash
3. implement Array.prototype.flat()JavaScript
2. implement curry() with placeholder support JavaScript
1. implement curry()JavaScript