sortedSquares.swift

    func sortedSquares(_ A: [Int]) -> [Int] {
        var res = [Int](repeating: 0, count: A.count)
        var index = A.count - 1
        var left = 0
        var right = A.count - 1
        while left <= right {
            var a = A[left] * A[left]
            var b = A[right] * A[right]
            if a > b {
                res[index] = a
                index -= 1
                left += 1
            } else {
                res[index] = b
                index -= 1
                right -= 1
            }
        }
        return res
    }