Quicksort playground

Quicksort.swift

import Darwin

func quickSort(inout data:[Int], _ left:Int, _ right:Int) {
    let index = partition(&data, left, right)
    
    if left < index - 1 {
        quickSort(&data, left, index - 1)
    }
    if index < right {
        quickSort(&data, index, right)
    }
}

func quickSort(inout data:[Int]) {
    quickSort(&data, 0, data.count - 1)
}

func partition(inout data:[Int], _ left:Int, _ right:Int) -> Int {
    let upto = UInt32(right - left + 1)
    let pivotRand:Int = Int(arc4random_uniform(upto)) + left
    
//    let pivot = (right + left) / 2
    let pivotVal = data[pivotRand]
    
    var leftT = left
    var rightT = right
    while leftT <= rightT {
        while data[leftT] < pivotVal {
            leftT += 1
        }
        while data[rightT] > pivotVal {
            rightT -= 1
        }
        if leftT <= rightT {
            swap(&data, leftT, rightT)
            leftT += 1
            rightT -= 1
        }
    }
    
    return leftT
}

func swap(inout data:[Int], _ left:Int, _ right:Int) {
    let leftVal = data[left]
    data[left] = data[right]
    data[right] = leftVal
}


// Test with some random data
var data = [Int]()
let max = 10
let maxVal = 100
for i in 0..<max {
    let sign = arc4random_uniform(2) == 0 ? -1 : 1
    
    data += [sign * Int(arc4random_uniform(UInt32(100)))]
}

print(data)
quickSort(&data)
print(data)