Day 12; Inheritance.swift

import Foundation

// Class Person
class Person {
    private let firstName: String
    private let lastName: String
    private let id: Int

    // Initializer
    init(firstName: String, lastName: String, id: Int) {
        self.firstName = firstName
        self.lastName = lastName
        self.id = id
    }

    // Print person data
    func printPerson() {
        print("Name: \(lastName), \(firstName)")
        print("ID: \(id)")
    }
} // End of class Person

// Class Student
class Student: Person {
    var testScores: [Int]
    
    init(firstName: String, lastName: String, id: Int, scores: [Int]) {
        self.testScores = scores
        super.init(firstName: firstName, lastName: lastName, id: id)
    }
    
    func calculate() -> Character {
        let average = testScores.reduce(0, +) / testScores.count
        if average >= 90 { return "O" }
        else if average >= 80 { return "E" }
        else if average >= 70 { return "A" }
        else if average >= 55 { return "P" }
        else if average >= 40 { return "D" }
        else { return "T" }
    }
} // End of class Student

let nameAndID = readLine()!.components(separatedBy: " ")
let _ = readLine()
let scores = readLine()!.components(separatedBy: " ").map{ Int($0)! }

let s = Student(firstName: nameAndID[0], lastName: nameAndID[1], id: Int(nameAndID[2])!, scores: scores)

s.printPerson()

print("Grade: \(s.calculate())")