Correct way to find max in an Array in Swift

Question

I\'ve so far got a simple (but potentially expensive) way:

var myMax = sort(myArray,>)[0]

And how I was taught to do it at school:

Answer 1

Updated for Swift 3/4:

Use below simple lines of code to find the max from array;

var num = [11, 2, 7, 5, 21]
var result = num.sorted(){
    $0 > $1
}
print("max from result: \(result[0])") // 21