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To fetch alternative even values from a JavaScript array, you need to iterate through the array and check if the index is even using the modulo operator. An index is even when index % 2 == 0. Syntax if (index % 2 == 0) { // This will select elements at even positions (0, 2, 4, ...) } Example The following example demonstrates how to fetch alternative even values from an array: var subjectsName = ["MySQL", "JavaScript", "MongoDB", "C", "C++", "Java"]; for (let index = 0; index ... Read More
Suppose we have an array of objects like this: const arr = [{ "value": 10, "id": "111", "name": "BlackCat", }, { "value": 10, "id": "111", "name": "BlackCat", }, { "value": 15, "id": "777", "name": "WhiteCat", }]; We are required to write a JavaScript function that takes in one such array. The function should then merge all those objects together that ... Read More
We are required to write a JavaScript function that takes in a string containing just the characters: '(', ')', '{', '}', '[' and ']' Our function should determine if the input string is valid. An input string is valid if: Open brackets must be closed by the same type of brackets. Open brackets must be closed in the correct order. ... Read More
We are required to write a JavaScript function that takes in an array of integers as the only argument. The function should first permute all possible subarrays from the original array that have an odd length. And then the function should find the combined sum of all the elements of those subarrays and return the sum. For example, if the input array is: const arr = [1, 2, 3]; Then the output should be: const output = 12; Because the desired subarrays are [1], [2], [3], [1, 2, 3] with ... Read More
Problem We need to write a JavaScript function that determines if a bus can accommodate all waiting passengers. The function takes three parameters: cap − the total capacity of people the bus can hold (excluding the driver) on − the number of people currently on the bus (excluding the driver) wait − the number of people waiting to board the bus If there's enough space for everyone, return 0. Otherwise, return the number of passengers who cannot board. Solution The logic is straightforward: calculate ... Read More
We need to find the length of the longest subarray where the difference between maximum and minimum values is exactly 1. This means the subarray can only contain two consecutive numbers (like 3 and 4) or just one unique number repeated. Problem Statement Given an array of numbers, find the length of the longest subarray where the difference between its maximum and minimum values is exactly 1. For example, with input array: const arr = [2, 4, 3, 3, 6, 3, 4, 8]; The longest valid subarray is [4, 3, 3, 3, 4] ... Read More
In this article, we are going to explore the 'in' operator and how to use it in JavaScript. The in operator is an inbuilt operator in JavaScript that is used for checking whether a particular property exists in an object or not. It will return true if the property exists, else false is returned. Syntax prop in object Parameters This operator accepts the following parameters as described below − prop − This parameter holds the string or symbol that represents a property ... Read More
In this tutorial, we'll be discussing how to get the sum of the powers of all the numbers from start to end in JavaScript. We'll be using the built-in Math.pow() method to calculate the powers and the Array reduce() method to sum up the values. Using the Math.pow() Method The Math.pow() method allows us to calculate the power of a number. We can use this method to calculate the powers of all the numbers from start to end. Syntax Math.pow(base, exponent); Parameters Base − The base number. ... Read More
In JavaScript, you can manipulate array length to clear memory and allocate new slots. When you set an array's length to 0, it clears all elements. Setting length to a larger value allocates empty slots. Understanding Array Length Property The length property controls how many elements an array can hold. Setting it to 0 removes all elements, while setting it to a larger number creates empty slots filled with undefined. var arrayObject = [ "John", "David", "Mike" ]; console.log("Original array:", arrayObject); console.log("Original ... Read More
We are required to write a JavaScript function that takes in an array of numbers. Our function should do the following two things: Make use of a recursive approach. Calculate the product of all the elements in the array. And finally, it should return the product. For example, if the input array is: const arr = [1, 3, 6, 0.2, 2, 5]; Then the output should be: 36 How Recursion Works Recursion breaks down the problem into smaller subproblems. For ... Read More