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JavaScript Coding Questions
As a Front-End developer, JavaScript is the core skill of everything
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Sort: most accepted
Difficulty: easy
1. implement curry()
JavaScript
easy
31534 accepted
6. implement basic debounce()
JavaScript
Lodash
easy
17037 accepted
19. find corresponding node in two identical DOM tree
JavaScript
easy
10598 accepted
11. what is Composition? create a pipe()
JavaScript
easy
9626 accepted
17. Create a simple store for DOM element
JavaScript
easy
8240 accepted
18. Improve a function
JavaScript
easy
7434 accepted
28. implement clearAllTimeout()
JavaScript
easy
7084 accepted
176. undefined to null
JavaScript
easy
6633 accepted
167. Intersection of unsorted arrays
JavaScript
Algorithm
easy
5610 accepted
25. Reorder array with new indexes
JavaScript
Algorithm
easy
5149 accepted
15. implement a simple DOM wrapper to support method chaining like jQuery
JavaScript
easy
5124 accepted
162. find the single integer
JavaScript
Algorithm
easy
4780 accepted
35. implement `Promise.race()`
JavaScript
easy
4538 accepted
155. create a count function
JavaScript
easy
4302 accepted
159. implement promisify()
JavaScript
easy
4188 accepted
148. create a counter object
JavaScript
easy
3878 accepted
154. Two-way binding
JavaScript
DOM
easy
3223 accepted
39. implement range()
JavaScript
easy
3150 accepted
91. invert a binary tree
JavaScript
Algorithm
easy
2914 accepted
37. implement Binary Search (unique)
JavaScript
easy
2664 accepted
89. Next Right Sibling
JavaScript
DOM
easy
2655 accepted
157. semver compare
JavaScript
easy
2617 accepted
31. implement async helper - `race()`
JavaScript
easy
2536 accepted
60. create your own `new` operator
JavaScript
easy
2509 accepted
47. reverse a linked list
JavaScript
Algorithm
easy
2384 accepted
40. implement Bubble Sort
JavaScript
Algorithm
easy
2311 accepted
145. most frequently occurring character
JavaScript
easy
2220 accepted
118. Virtual DOM II - createElement
JavaScript
easy
2061 accepted
133. roman numerals to integer
JavaScript
easy
2045 accepted
163. integer to roman numerals
JavaScript
Algorithm
easy
1954 accepted
81. merge sorted arrays
JavaScript
Algorithm
easy
1876 accepted
121. A number sequence
JavaScript
easy
1825 accepted
107. Find the largest difference
JavaScript
Algorithm
easy
1822 accepted
105. find the first duplicate character in a string
JavaScript
string
easy
1811 accepted
38. implement `jest.spyOn()`
JavaScript
easy
1788 accepted
48. search first index with Binary Search(possible duplicate array)
JavaScript
Algorithm
easy
1691 accepted
102. validate string of parentheses
JavaScript
Algorithm
string
easy
1676 accepted
106. Find two numbers that sum up to 0
JavaScript
Algorithm
easy
1650 accepted
94. implement your own `Object.create`
JavaScript
easy
1646 accepted
120. create `isPrime()`
JavaScript
Algorithm
easy
1643 accepted
138. Intersection of two sorted arrays
JavaScript
Algorithm
easy
1622 accepted
87. longest substring with unique characters
JavaScript
Algorithm
easy
1610 accepted
54. flatten Thunk
JavaScript
easy
1563 accepted
140. Virtual DOM III - Functional Component
JavaScript
easy
1536 accepted
97. compress a string
JavaScript
string
easy
1493 accepted
49. search last index with Binary Search(possible duplicate array)
JavaScript
Algorithm
easy
1381 accepted
109. implement `Math.pow()`
JavaScript
Algorithm
easy
1373 accepted
116. implement Object.is()
JavaScript
easy
1369 accepted
42. implement Insertion Sort
JavaScript
Algorithm
easy
1351 accepted
93. Generate Fibonacci Number with recursion
JavaScript
easy
1223 accepted
147. Pick up stones
JavaScript
easy
1222 accepted
100. detect circle in linked list
JavaScript
Algorithm
easy
1189 accepted
44. implement Selection Sort
JavaScript
Algorithm
easy
1154 accepted
50. search element right before target with Binary Search(possible duplicate array)
JavaScript
Algorithm
easy
1143 accepted
51. search element right after target with Binary Search(possible duplicate array)
JavaScript
Algorithm
easy
976 accepted
96. count "1" in binary form
JavaScript
easy
908 accepted
62. implement BigInt addition
JavaScript
Algorithm
easy
883 accepted
142. lit-html 1 - tagged templates
JavaScript
lit-html
easy
697 accepted
72. implement Observable interval()
JavaScript
easy
496 accepted
74. implement Observable Transformation Operators
JavaScript
easy
443 accepted
73. implement Observable fromEvent()
JavaScript
easy
428 accepted
141. implement btoa()
JavaScript
easy
278 accepted