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Saqib Jamil
Saqib Jamil

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5 Javascript coding interview questions - Part 2

Javascript coding interview questions part 1
Javascript coding interview questions part 3

1: Two Sum - Given an array of integers nums and an integer target, return the indices of the two numbers that add up to the target.

function twoSum(nums, target) { const numMap = new Map(); for (let i = 0; i < nums.length; i++) { const complement = target - nums[i]; if (numMap.has(complement)) { return [numMap.get(complement), i]; } numMap.set(nums[i], i); } return null; // If no such pair exists } // Test console.log(twoSum([2, 7, 11, 15], 9)); // Output: [0, 1] 
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2: Find the Largest Number in an Array:
Write a function that takes an array of numbers as input and returns the largest number.

function findLargestNumber(arr) { return Math.max(...arr); } // Test console.log(findLargestNumber([3, 5, 1, 9, 2])); // Output: 9 
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3: Find the Longest Word
Write a function that takes a sentence as input and returns the longest word in the sentence.

function findLongestWord(sentence) { const words = sentence.split(' '); let longestWord = ''; for (const word of words) { if (word.length > longestWord.length) { longestWord = word; } } return longestWord; } // Test console.log(findLongestWord('The quick brown fox jumped over the lazy dog')); // Output: "jumped" 
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4: Count Vowels
Write a function that takes a string as input and returns the number of vowels (a, e, i, o, u) in the string.

function countVowels(str) { const vowels = str.match(/[aeiou]/gi); return vowels ? vowels.length : 0; } // Test console.log(countVowels('Hello World')); // Output: 3 
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5: Find Missing Number
Write a function that takes an array containing integers from 1 to n (excluding one number) and returns the missing number.

function findMissingNumber(nums) { const n = nums.length + 1; const totalSum = (n * (n + 1)) / 2; const currentSum = nums.reduce((sum, num) => sum + num, 0); return totalSum - currentSum; } // Test console.log(findMissingNumber([1, 2, 4, 5])); // Output: 3 
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Javascript coding interview questions part 1
Javascript coding interview questions part 3

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