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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
tag: JavaScript
1. implement curry()
JavaScript
easy
21163 accepted
3. implement Array.prototype.flat()
JavaScript
easy
17208 accepted
6. implement basic debounce()
JavaScript
Lodash
easy
11704 accepted
19. find corresponding node in two identical DOM tree
JavaScript
easy
8498 accepted
11. what is Composition? create a pipe()
JavaScript
easy
6569 accepted
17. Create a simple store for DOM element
JavaScript
easy
6336 accepted
28. implement clearAllTimeout()
JavaScript
easy
5497 accepted
18. Improve a function
JavaScript
easy
5476 accepted
176. undefined to null
JavaScript
easy
4836 accepted
23. create a sum()
JavaScript
easy
4449 accepted
167. Intersection of unsorted arrays
JavaScript
Algorithm
easy
4358 accepted
162. find the single integer
JavaScript
Algorithm
easy
3924 accepted
15. implement a simple DOM wrapper to support method chaining like jQuery
JavaScript
easy
3837 accepted
25. Reorder array with new indexes
JavaScript
Algorithm
easy
3693 accepted
155. create a count function
JavaScript
easy
3469 accepted
159. implement promisify()
JavaScript
easy
3212 accepted
35. implement `Promise.race()`
JavaScript
easy
3130 accepted
148. create a counter object
JavaScript
easy
3086 accepted
154. Two-way binding
JavaScript
DOM
easy
2725 accepted
91. invert a binary tree
JavaScript
Algorithm
easy
2432 accepted
39. implement range()
JavaScript
easy
2335 accepted
89. Next Right Sibling
JavaScript
DOM
easy
2272 accepted
157. semver compare
JavaScript
easy
2180 accepted
60. create your own `new` operator
JavaScript
easy
1949 accepted
37. implement Binary Search (unique)
JavaScript
easy
1918 accepted
47. reverse a linked list
JavaScript
Algorithm
easy
1815 accepted
145. most frequently occurring character
JavaScript
easy
1810 accepted
46. implement `_.once()`
JavaScript
Lodash
easy
1786 accepted
31. implement async helper - `race()`
JavaScript
easy
1751 accepted
163. integer to roman numerals
JavaScript
Algorithm
easy
1635 accepted
133. roman numerals to integer
JavaScript
easy
1596 accepted
118. Virtual DOM II - createElement
JavaScript
easy
1569 accepted
40. implement Bubble Sort
JavaScript
Algorithm
easy
1566 accepted
121. A number sequence
JavaScript
easy
1419 accepted
105. find the first duplicate character in a string
JavaScript
string
easy
1411 accepted
107. Find the largest difference
JavaScript
Algorithm
easy
1403 accepted
81. merge sorted arrays
JavaScript
Algorithm
easy
1369 accepted
138. Intersection of two sorted arrays
JavaScript
Algorithm
easy
1353 accepted
94. implement your own `Object.create`
JavaScript
easy
1346 accepted
38. implement `jest.spyOn()`
JavaScript
easy
1307 accepted
120. create `isPrime()`
JavaScript
Algorithm
easy
1278 accepted
106. Find two numbers that sum up to 0
JavaScript
Algorithm
easy
1275 accepted
102. validate string of parentheses
JavaScript
Algorithm
string
easy
1266 accepted
48. search first index with Binary Search(possible duplicate array)
JavaScript
Algorithm
easy
1202 accepted
97. compress a string
JavaScript
string
easy
1180 accepted
140. Virtual DOM III - Functional Component
JavaScript
easy
1175 accepted
87. longest substring with unique characters
JavaScript
Algorithm
easy
1166 accepted
54. flatten Thunk
JavaScript
easy
1136 accepted
109. implement `Math.pow()`
JavaScript
Algorithm
easy
1061 accepted
116. implement Object.is()
JavaScript
easy
1059 accepted
49. search last index with Binary Search(possible duplicate array)
JavaScript
Algorithm
easy
1005 accepted
93. Generate Fibonacci Number with recursion
JavaScript
easy
955 accepted
147. Pick up stones
JavaScript
easy
938 accepted
100. detect circle in linked list
JavaScript
Algorithm
easy
931 accepted
42. implement Insertion Sort
JavaScript
Algorithm
easy
927 accepted
44. implement Selection Sort
JavaScript
Algorithm
easy
795 accepted
50. search element right before target with Binary Search(possible duplicate array)
JavaScript
Algorithm
easy
793 accepted
51. search element right after target with Binary Search(possible duplicate array)
JavaScript
Algorithm
easy
724 accepted
96. count "1" in binary form
JavaScript
easy
691 accepted
62. implement BigInt addition
JavaScript
Algorithm
easy
653 accepted
142. lit-html 1 - tagged templates
JavaScript
lit-html
easy
520 accepted
72. implement Observable interval()
JavaScript
easy
395 accepted
74. implement Observable Transformation Operators
JavaScript
easy
368 accepted
73. implement Observable fromEvent()
JavaScript
easy
359 accepted
141. implement btoa()
JavaScript
easy
228 accepted