import UIKit

class ViewController: UIViewController {

    func plus(num1: Int, num2: Int) -> Int {
        let result = num1 + num2
        return result
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        let a = 10
        let b = 20
        let sum = plus(num1: a, num2: b)
        print(sum)
    }
}