Scala Array.view memory usage

Question

I'm learning Scala and have been trying some LeetCode problems with it, but I'm having trouble with the memory limit being exceeded. One problem I have tried goes like this:

A swap is defined as taking two distinct positions in an array and swapping the values in them.

A circular array is defined as an array where we consider the first element and the last element to be adjacent.

Given a binary circular array nums, return the minimum number of swaps required to group all 1's present in the array together at any location.

and my attempted solution looks like

object Solution {
    def minSwaps(nums: Array[Int]): Int = {
        val count = nums.count(_==1)
        if (count == 0) return 0
        val circular = nums.view ++ nums.view
        circular.sliding(count).map(_.count(_==0)).min
    }
}

however, when I submit it, I'm hit with Memory Limit Exceeded for one of the test case where nums is very large.

My understanding is that, because I'm using .view, I shouldn't be allocating over O(1) memory. Is that understanding incorrect? To be clear, I realise this is the most time efficient way of solving this, but I didn't expect it to be memory inefficient.

The version used is Scala 2.13.7, in case that makes a difference.

Update

I did some inspection of the types and it seems circular is only a View unless I replace ++ with concat which makes it IndexedSeqView, why is that, I thought ++ was just an alias for concat?

If I make the above change, and replace circular.sliding(count) with (0 to circular.size - count).view.map(i => circular.slice(i, i + count)) it "succeeds" in hitting the time limit instead, so I think sliding might not be optimised for IndexedSeqView.