Compile time polymorphism

class Arithmetic {
    func add(_ valueA: Int, _ valueB: Int) -> Int {
        return valueA + valueB
    }
    
    func add(_ valueA: UInt64, _ valueB: UInt64) -> UInt64 {
        return valueA + valueB
    }
    
    func add(_ valueA: Int, _ valueB: UInt64) -> UInt64 {
        return UInt64(valueA) + valueB
    }
    
    func add(_ valueA: UInt64, _ valueB: Int) -> UInt64 {
        return valueA + UInt64(valueB)
    }
}