A left rotation operation on an array shifts each of the array's elements unit to the left. Given an array of integers and a number, perform left rotations on the array. Return the updated array to be printed as a single line of space-separated integers.

ArrayLeftRotation.swift

func rotLeft(a: [Int], d: Int) -> [Int] {
    var array: [Int] = []
    for i in 0 ..< a.count {
        let index = (i + d) % a.count
        array.append(a[index])
    }
    return array
}


rotLeft(a: [1,2,3,4,5], d: 4) // output [5, 1, 2, 3, 4]