Split large Array in Array of two elements

Question

I have large list of objects and I need to split them in a group of two elements for UI propouse.

Example:

[0, 1, 2, 3, 4, 5, 6]

Becomes

Answer 1

Alternatively, you can use reduce for this, but this is probably not the most efficient:

let res = a.reduce([[Int]]()) { (var acc: [[Int]], current: Int) in

    if acc.last != nil && acc.last?.count < 2 {
        var newLast = acc.last
        newLast?.append(current)
        acc.removeLast()

        acc.append(newLast!)
    } else {
        acc.append([current])
    }
    return acc
}