arrays - 快速数组存储数据

Question

我创建了一个返回多个值的函数

let interestingNumbers = [   // String:Array<Int>
    "Prime": [2, 3, 5, 7, 11, 23],
    "Fibonacci": [1, 1, 2, 3, 5, 80],
    "Square": [1, 4, 9, 16, 25],
]
func largestNum(objDictionary:[String:Array<Int>]) -> (Int,String) {
var largest = 0
var ki:String? = nil
for (kind, numbers) in interestingNumbers {
    for number in numbers {
        if number > largest {
            largest = number
            ki=kind
        }
    }
    }
    return (largest , ki!)
}

print(largestNum(interestingNumbers)) //calling fuction and print

/*var ar2:[Int,String] = largestNum(interestingNumbers))

print(ar2)*/' this code have an error`

如何将函数的返回值存储在数组中

Answer 1

更新:

如果您希望两个值都位于一个数组中 ar[0]是Int和ar[1]是String ，那么你需要声明 ar2成为[Any]并在初始化时解压元组 ar2 :

let largest = largestNum(interestingNumbers)
var ar2:[Any] = [largest.0, largest.1]

print(ar2) // [80, "Fibonacci"]

如果您只是将返回值分配给 ar2并将其保留为元组，您可以使用 ar2.0 访问值和ar2.1 :

var ar2 = largestNum(interestingNumbers)
print(ar2.0)  //  80
print(ar2.1)  //  "Fibonacci"

或者如果您更改 largestNum返回命名元组:

func largestNum(objDictionary:[String:Array<Int>]) -> (number: Int, kind: String) {
}

var ar2 = largestNum(interestingNumbers)
print(ar2.number)  //  80
print(ar2.kind)    // "Fibonacci"

<小时/>

原始答案:

声明你的数组ar2保存 Int 的元组对和String ，然后将返回值包装在 [] 中创建数组:

var ar2:[(Int,String)] = [largestNum(interestingNumbers)]

print(ar2)  // [(80, "Fibonacci")]

<小时/>

因为元组实际上是用于临时值的，所以使用 struct 将值存储在数组中是更好的方式。 :

更改您的函数以返回 InterestingNumber :

struct InterestingNumber {
    let kind: String
    let number: Int
}

func largestNum(objDictionary:[String:Array<Int>]) -> InterestingNumber {
    // contents omitted for brevity

    return InterestingNumber(kind: ki!, number: largest)
}


let largest = largestNum(interestingNumbers)

// Define your array to hold `InterestingNumber`s:   
var ar2:[InterestingNumber] = [largest]

print(ar2)  // [InterestingNumber(kind: "Fibonacci", number: 80)]

<小时/>

如果您的意思是 ar2仅保存单个值，然后只需执行以下操作:

var ar2 = largestNum(interestingNumbers)

Swift 将推断类型(它是原始代码中的元组，或者使用 InterestingNumber 时的 struct 。