func example(str: String, isAction: Bool = true, action: () -> Void) {
    print("---------\(str), isAction: \(isAction)---------")
    
    if isAction {
        action()
    }
}

func quicksort<T: Comparable>(_ a: [T]) -> [T] {
    guard a.count > 1 else { return a }
    
    let pivot = a[a.count/2]
    let less = a.filter { $0 < pivot }
    let equal = a.filter { $0 == pivot }
    let greater = a.filter { $0 > pivot }
    print("\nArray: \(a) \nless: \(less) \nequal: \(equal) \ngreater: \(greater)\nresult:\(less+equal+greater)")
    
    return quicksort(less) + equal + quicksort(greater)
}

example(str: "Quick Sort") {
    let x = createRandomArray(numberOfElements: 10)
    quicksort(x)
}