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We are required to write a JavaScript function that takes in a number and returns the difference of the sums of the digits at even place and the digits odd place.ExampleThe code for this will be −const num = 123456; const alternateDifference = (num, res = 0, ind = 0) => { if(num){ if(ind % 2 === 0){ res += num % 10; }else{ res -= num % 10; }; return alternateDifference(Math.floor(num / 10), res, ++ind); }; return Math.abs(res); }; console.log(alternateDifference(num));OutputThe output in the console −3
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
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
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
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
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 ]
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
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
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
Simply use, array_merge() to concatenate two arrays in PHP. Let’s say the following are out arrays −$nameArray1 = array('John','David'); $nameArray2 = array('Mike','Sam');Now, set both the above arrays in array_merge() to concatenate them.The syntax is as follows −array_merge($yourFirstArrayName, $yourSecondArrayName);ExampleThe PHP code is as follows Live Demo OutputThis will produce the following outputArray ( [0] => John [1] => David [2] => Mike [3] => Sam )