Quick Sort.

Quick Sort have Five ways to be implemented. We will preview them individually. 
We'll start with the most Popular one which is Lomuto's partitioning algorithm. 
For more Details look at https://en.wikipedia.org/wiki/Quicksort#Lomuto_partition_scheme

func quikcSort(inout list : [Int] , low : Int , high : Int) {
    if low < high {
        let pIndex = partition(&list, low: low, high: high)
        quikcSort(&list, low: low, high: pIndex-1)
        quikcSort(&list, low: pIndex + 1, high: high)
    }
}

func partition(inout list : [Int], low: Int, high : Int) -> Int {
    let pivot = list[high]
    var j = low
    var i = j - 1
    while j < high {
        if list[j] <= pivot{
            i += 1
            (list[i], list[j]) = (list[j], list[i])
						}
        j += 1
    }
    (list[i+1], list[high]) = (list[high], list[i+1])
    return i+1
}

var list = [7,3,15,10,0,8,2,4]
quikcSort(&list, low: 0, high: list.count-1)

var list2 = [ 10, 0, 3, 9, 2, 14, 26, 27, 1, 5, 8, -1, 8 ]
quikcSort(&list2, low: 0, high: list2.count-1)

var list3 = [1,3,9,8,2,7,5]
quikcSort(&list3, low: 0, high: list3.count-1)