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Found 6710 Articles for Javascript

208 Views
We have an array of numbers like this −const arr = [-1,-2,-1,0,-1,-2,-1,-2,-1,0,1,0];We are required to write a JavaScript function that counts the consecutive groups of negative numbers in the array.ExampleThe code for this will be −const arr = [-1,-2,-1,0,-1,-2,-1,-2,-1,0,1,0]; const countClusters = arr => { return arr.reduce((acc, val, ind) => { if(val < 0 && arr[ind+1] >= 0){ acc++; }; return acc; }, 0); }; console.log(countClusters(arr));OutputThe output in the console −2

201 Views
We are required to write a JavaScript function that computes the Factorial of a number n by making use of recursive approach.ExampleThe code for this will be −const num = 9; const recursiceFactorial = (num, res = 1) => { if(num){ return recursiceFactorial(num-1, res * num); }; return res; }; console.log(recursiceFactorial(num)); console.log(recursiceFactorial(6)); console.log(recursiceFactorial(10)); console.log(recursiceFactorial(5)); console.log(recursiceFactorial(13));OutputThe output in the console −362880 720 3628800 120 6227020800

878 Views
Two numbers are said to be co-primes if there exists no common prime factor amongst them (1 is not a prime number).We are required to write a function that takes in two numbers and returns true if they are coprimes otherwise returns false.ExampleThe code for this will be −const areCoprimes = (num1, num2) => { const smaller = num1 > num2 ? num1 : num2; for(let ind = 2; ind < smaller; ind++){ const condition1 = num1 % ind === 0; const condition2 = num2 % ind === 0; ... Read More

478 Views
We are required to write a JavaScript function that finds how many times a specific letter is appearing in the sentence.ExampleThe code for this will be −const string = 'This is just an example string for the program'; const countAppearances = (str, char) => { let count = 0; for(let i = 0; i < str.length; i++){ if(str[i] !== char){ // using continue to move to next iteration continue; }; // if we reached here it means that str[i] and char ... Read More

511 Views
We are required to write a JavaScript function that takes in an array of Numbers and returns a new array with elements as the sum of two consecutive elements from the original array.For example, if the input array is −const arr1 = [1, 1, 2, 7, 4, 5, 6, 7, 8, 9];Then the output should be −const output = [2, 9, 9, 13, 17]ExampleThe code for this will be −const arr11 = [1, 1, 2, 7, 4, 5, 6, 7, 8, 9]; const consecutiveSum = arr => { const res = []; for(let i = 0; i < arr.length; i += 2){ res.push(arr[i] + (arr[i+1] || 0)); }; return res; }; console.log(conseutiveSum(arr1));OutputThe output in the console −[ 2, 9, 9, 13, 17 ]

238 Views
We are required to write a JavaScript function that takes in two arrays of Numbers and checks whether all the elements of the first array exist in the second or not.ExampleThe code for this will be −const arr1 = [34, 78, 89]; const arr2 = [78, 67, 34, 99, 56, 89]; const multipleIncludes = (first, second) => { const indexArray = first.map(el => { return second.indexOf(el); }); return indexArray.indexOf(-1) === -1; } console.log(multipleIncludes(arr1, arr2));OutputThe output in the console −true

262 Views
We are required to write a function that takes in two arguments, first is a string and second is a number. The length of string is always less than or equal to the number. We have to insert some random lowercase alphabets at the end of the string so that its length becomes exactly equal to the number and we have to return the new string.ExampleLet’s write the code for this function −const padString = (str, len) => { if(str.length < len){ const random = Math.floor(Math.random() * 26); const randomAlpha = String.fromCharCode(97 + ... Read More

434 Views
We have an array that contains String and number mixed data types, we have to write a sorting function that sorts the array so that the NaN values always end up at the bottom.The array should contain all the valid numbers in the front, followed by string literals, followed by NaN.The code for this will be −const arr = [344, 'gfd', NaN, '', 15, 'f', 176, NaN, 736, NaN, 872, 859, 'string', 13, 'new', NaN, 75]; const sorter = (a, b) => { if(a !== a){ return 1; }else if(b !== b){ ... Read More

393 Views
We are required to write a function that takes in an array and returns an object with two arrays positive and negative. They both should be containing all positive and negative items respectively from the array.We will be using the Array.prototype.reduce() method to pick desired elements and put them into an object of two arrays.ExampleThe code for this will be −const arr = [97, -108, 13, -12, 133, -887, 32, -15, 33, -77]; const splitArray = (arr) => { return arr.reduce((acc, val) => { if(val < 0){ acc['negative'].push(val); }else{ ... Read More

241 Views
We are required to write a JavaScript function that takes in an array of numbers as the first argument and a number as the second argument. The function should then return the number from the array which closest to the number given to the function as second argument.ExampleThe code for this will be −const arr = [3, 56, 56, 23, 7, 76, -2, 345, 45, 76, 3]; const num = 37 const findClosest = (arr, num) => { const creds = arr.reduce((acc, val, ind) => { let { diff, index } = acc; ... Read More