How to divide one array into two half arrays in swift-CodePudding

I have one array. I need to divide that array into two halves; first half in one array, second in another.

tried code:

let totalArray = [20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10]

var firstArray = [Int]()
var secondArray = [Int]()

for i in totalArray.indices {
    if i <= totalArray.count/2 {
        firstArray.append(contentsOf: [i])
    } else {
        secondArray.append(contentsOf: [i])
    }
}

o/p:

[0, 1, 2, 3, 4, 5]
[6, 7, 8, 9, 10]

But I need it like this:

firstArray = [20, 19, 18, 17, 16, 15]
secondArray = [14, 13, 12, 11, 10]

What am I doing wrong?

CodePudding user response：

You are appending the indices rather than the values (see howaldoliverdev's answer).

But this is Swift. There are more convenient ways to split the array for example

let totalArray = [20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10]

let mid = (totalArray.count   1) / 2

let firstArray = Array(totalArray[..<mid])
let secondArray = Array(totalArray[mid...])

CodePudding user response：

contentsOf gives you the content of "i" itself, which carries the index number (the position of the array item), not the respective value of the array item.

You want:

firstArray.append(totalArray[i])

secondArray.append(totalArray[i])

That way, you get back the value from the array item at the respective position.