Had the same approach but couldn't solve the problem using it, seeing your code now I realize I was doing splice to arr[i] instead of i LOL

Why we iterate from i = arr.length-1 ?

Iterating from the end, why didn't I think abt it

What do you think .filter does?

this can be done in one pass. linear time. splicing and pushing to the end is no longer linear time because splicing and re-indexing the array is like an inner loop within the for-loop, making the time complexity quadratic.

It's not "iterating and removing".
It's "iterating, removing and adding".
That's why the cached index remains valid.

why not? I like this solution?

Can you explain why iterating and removing items from the array is bad practice?
My solution is pretty similar to this.

Iterating from the end... Yep, that's clever)

Debatable, this solution does win in space complexity.

You shouldn't iterate through an array and remove from it at the same time, even if doing it from the end works.

well i guess you can't be blamed. the tests don't enforce immutability.