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Tag: arrays

What does it mean by “second += arr[i][arr.length-i-1]”

I been practicing my algorithm solving skill by solving HackerRank problems. However, one of the problems is giving me a difficult time to understand. It is about calculating absolute difference between sum of diagonals in a square matrix “arr”. If the square matrix is like this: and the solution is like this: So, I came up with this solution: However,

Getting array of school values from all objects using JS

Hello I am new to the JavaScript language. I have a property that’s an array of objects with data about a school like: Can I perhaps get an array of the telephone values from all the objects using JS? Please help. Answer All you need to do it traverse the items in the data, while grabbing the telephone field

jQuery sort() is not working in function()

I am trying to sort the array after adding new entry into the array using push(). However there are 2 errors. First the sort() is not allowed. Second is when I remove the sort() the new entry always showed with a number of 5 attached Answer When adding new object into an array, you only need to use arr.push(obj), and

Filter array of infinitely nested objects

Let’s say I have an array of nested objects such as: And I would like to return a new array with id: 3 excluded for example. So it would become: The excluded id can be from any level, and it and its children should be removed. What’s the best approach to do this? I’ve tried several other solutions with no

How to write this function with forEach?

I am trying to group the people by their age and as you can see, my code works with the reduce method. I managed to get this working but now I want to do the same with forEach method. Here’s my code: Answer Reduce accepts initial value that you update each iteration and return. So if you wish to use

Filter an array nested within an object

I was able to find many sources saying how to filter nested arrays, but all of these referred to arrays within arrays. In my case, there’s an array nested within an object and I can’t figure out how to deal with it. The source array is: How to filter the nested array so that the resulting object looks like: So,