arrays - 对角数组求和

Question

我怎样才能在对角线 3 个数组中求和？

例子：

[ 6 , 6 , 5 ]

[10, 5 , 10]

[ 3 , 20, 1 ]

从左到右，从右到左

6 + 5 + 1 = 12

3 + 5 + 5 = 13

这就是我的数组的声明方式：

@IBOutlet weak var text1: UITextField!


 let text : String = text1.text!
    var digits = [Int]()
    for element in text.characters
    {
        digits.append(Int(String(element))!)
    }
    print(digits)

这就是我的数组对角线求和的方式

 let anArray = [[digits],[digits2],[digits3]]
    let size = anArray.count
    for i in 0..<size {
        if anArray[i].count != size {
            print("error")
        }
    }


    var diagSum = 0
    for i in 0..<size {
        for j in 0..<size where i == j {
            diagSum += anArray[i][j] // i have an error here Cannot convert value of type '[Int]' to expected argument type 'Int'
        }
    }

标签： arraysswift

Answer 1

你可以试试

let arr1 = [[1,2,3],[1,2,3],[1,2,3]]
var sum = 0
arr1.indices.forEach { sum += arr1[$0][$0] }

---

arr1.indices.forEach { sum += arr1[$0][arr1.count - 1 - $0] } // not compiled