rotateArray.swift

func rotateLeft(arr:[Int], d:Int)->[Int] {
    if arr.count == 0 {
        return arr
    }
    
    let distanceToMove = d % arr.count
    var index = 0
    var tmpValue:Int? = arr[0]
    var tmpArr = arr
    for _ in 0..<tmpArr.count {
        let tmpIndex = ((index - distanceToMove) < 0 ? arr.count + (index - distanceToMove) : index - distanceToMove)
        if let value = tmpValue {
            tmpValue = arr[tmpIndex]
            tmpArr[tmpIndex] = value
        }
        index = tmpIndex
    }
    return tmpArr
}

var sample:[Int] = [1,2,3,4,5]
rotateLeft(arr: sample, d: 1)