Javascript developer Interview Questions


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Javascript Developer was asked...August 7, 2019

Convert : person_First_Name to personFirstName

4 Answers

var name = "person_First_Name"; var d = name.split("_").join(""); console.log(d); Less


function convertor(name){ let result="" splittedNames=name.split("_")>{ result+=a }) console.log(result); } convertor("Person_First_Name") Less

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Dassault Systemes

4)write program to remove duplicate in an array

4 Answers

function removeDuplicateUsingSet(arr){ let unique_array = Array.from(new Set(arr)) return unique_array } Less

var chars1 = ['A', 'B', 'A', 'C', 'B']; var uniqueChars2 = []; chars1.forEach((c) => { if(!uniqueChars2.includes(c)) { uniqueChars2.push(c); } }) Less

for(let i=0; i

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How will you put a child div in center to outer container?

2 Answers

{display:block; margin:0 auto;}

Margin : auto

Dassault Systemes

6) what will be the value of a and b if Var a = 5 +7 + “8” Var b = “8”+5+7

3 Answers


a = 128 b= 857

a=128 b=124

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Q : About Basic tech knowledge and one good assignment

2 Answers


Please do assignment carefully

Dassault Systemes

2)How to clear an array by different way

2 Answers

A = []; orelse; A .length=0; orelse; loop it till length is 0 and pop all elements Less

arr.splice(0, arr.length)

Capital One

To reverse a string without using reverse keyword.

2 Answers

Can use the loop in structure



Using a nested for() loop is inefficient, can you do it more efficient than the native String.indexOf() method? Without nesting for loops or recursion.

2 Answers

Convert the strings to objects with each word being added as a property to speed up the lookup. I had heard of this technique but never done it myself. Less

sort the words will be done in n Log n . for each word in 1st string do binary search on other string which will run in n log n so overall complexity will be n log n. Less


Online : 1) Nearest to zero element in an array 2) Longest prefix program 3) single loop reversal of string online questions require you to fill the logic only , not to write the entire program Pen paper : input =['acr', 'bat','car','atb','rca','rac','xyz'] desired output: [ ['acr','car','rca','rac'], ['bat','atb'],['xyz']] i.e grouping of psuedonyms .

1 Answers

let arr = ["acr", "bat", "car", "atb", "rca", "rac", "xyz"]; let flag = 0; let result = []; let pos = 0; for (let i = 0; i < arr.length; i++) { if (!result.flat().includes(arr[i])) { result.push([arr[i]]); pos += 1; for (let j = i + 1; j < arr.length; j++) { if (arr[i].length === arr[j].length) { for (let k = 0; k < arr[i].length; k++) { if (arr[j].includes(arr[i][k])) { flag += 1; } } if (flag == arr[i].length) { result[pos - 1].push(arr[j]); } flag = 0; } } } } console.log(result); Less

Pair programming exercise on a React Router related bug.

2 Answers

I tried rooftop slushie mentioned above and it was pretty helpful. I recommend it. Less

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