Quicksort: Iterative or Recursive

Question

I learnt about quick sort and how it can be implemented in both Recursive and Iterative method.
In Iterative method:

1. Push the range (0...n) into the stac

Answer 1

That's the solution i came up with in Javascript. I think it works.

function qs_iter(items) {
    if (!items || items.length <= 1) {
        return items
    }
    var stack = []
    var low = 0
    var high = items.length - 1
    stack.push([low, high])
    while (stack.length) {
        var range = stack.pop()
        low = range[0]
        high = range[1]
        if (low < high) {
            var pivot = Math.floor((low + high) / 2)
            stack.push([low, pivot])
            stack.push([pivot+1, high])
            while (low < high) {
                while (low < pivot && items[low] <= items[pivot]) low++
                while (high > pivot && items[high] > items[pivot]) high--
                if (low < high) {
                    var tmp = items[low]
                    items[low] = items[high]
                    items[high] = tmp
                }
            }
        }
    }
    return items
}

Let me know if you found a mistake :)