Removing a specific element from nested arrays

JavaScript
1

So I thought I had this challenge sorted, quite a good one.

I believe I used a nested for loop properly so each element inside every array inside the outer array is checked.

Your code so far




function filteredArray(arr, elem) {
  let newArr = [];

for ( var row = 0 ; row < arr.length ; row ++ ) {
  for (var col = 0; col< arr[row].length; col++) {

    if (arr[row][col] == elem) {

      delete arr[row][col];

    }

  }
}

newArr = arr;

  // change code above this line
  return newArr;
}

// change code here to test different cases:
console.log(filteredArray([[3, 2, 3], [1, 6, 3], [3, 13, 26], [19, 3, 9]], 3));

Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-data-structures/iterate-through-all-an-arrays-items-using-for-loops

so

 if (arr[row][col] == elem) {

      delete arr[row][col];
}

is using delete a legit way of getting rid of elem = 3 if it exists in any of the arrays?
Would be great if .pop() was able to specify what to remove but alas it can only remove the last element of an array.

I also think

newArr = arr;

may not be in the correct position.

Please give some pointers if I’m anywhere close - or not. Thansk in advance

2

delete removes properties from objects. It’s not what you want to use to remove an element from an array.

1 Like
3

Ah…

It must be splice() that should be in the if statement then?

4

That’d be the usual way to do it :slight_smile:

1 Like
5

So I think…

arr[row].splice(0, b);

Now, the question is - how to determine what b is here? The elem=3’s position is not fixed and is different for each of the nested arrays…

6

Would this work?

   const elemLocation = arr[row].indexOf(elem);
     arr[row].splice(elemLocation,1);
7

Try it out and see if it does what you expect :smiley: