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iOS

Posted by Lana Wong
Lana Wong
3,968 Points

Can anyone explain?

Can someone please describe, in detail, of what this code is doing. Thanks! :)

//Using tuples to make compound values
func calculateStatistics (scores: [Int]) ->
        (min: Int, max: Int, sum: Int){
    var min = scores[0]
    var max = scores[0]
    var sum = 0

    for score in scores{
        if score > max{
        max = score
        }else if score < min {
        min = score
        }
    sum += score
            }
return (min, max, sum)
}

let statistics = calculateStatistics([5, 3, 100, 3, 9])

print(statistics.sum)

print(statistics.2)

1 Answer

Anthony Boutinov
Anthony Boutinov
13,844 Points
Anthony Boutinov
Anthony Boutinov
13,844 Points 
func calculateStatistics (scores: [Int]) ->
        (min: Int, max: Int, sum: Int){ ...

This method takes an array of integers (scores) and returns a tuple (tuples are structs, basically). The tuple contains min, max, and sum properties.

Inside the method, min, max, and sum values are calculated and we return a tuple that consists of those values.

We call this method on an array of integers and assign the resulting tuple to a constant.

We print sum property of that tuple.

We print third property (numeration starts from 0, as always) of that tuple (which happens to be sum). Under the hood, a tuple, as I said above, is a struct. But it has some additional "abilities", namely the ability to access its properties using the notation we see here in the last line of code.

Anthony Boutinov
Anthony Boutinov
13,844 Points

To achieve similar behavior in other languages, we would have to define a struct, like that:

struct StatisticsTuple {
   let min: Int
   let max: Int
   let sum: Int
}

and have the method be rewritten like that:

func calculateStatistics (scores: [Int]) -> StatisticsTuple {
   //...
   return StatisticsTuple(min: min, max: max, sum: sum)
}

But we wouldn't be able to do this:

print(statistics.2)