import Foundation

// Define a class for Student

class Student {

    let name: String

    var grades: [Int]

    init(name: String, grades: [Int]) {

        self.name = name

        self.grades = grades

    }

    func averageGrade() -> Double {

        let total = grades.reduce(0, +) // Sum all grades

        return grades.isEmpty ? 0.0 : Double(total) / Double(grades.count)

    }

}

// Define a class for Classroom

class Classroom {

    let className: String

    var students: [Student]

    // Initializer

    init(className: String, students: [Student] = []) {

        self.className = className

        self.students = students

    }

    // Function to add a student

    func addStudent(_ student: Student) {

        students.append(student)

    }

    // Function to display average grades of all students

    func displayAverageGrades() {

        print("Classroom: \(className)")

        students.forEach { student in

            let average = student.averageGrade()

            print("\(student.name)'s average grade: \(average)")

        }

    }

}

// Usage

let student1 = Student(name: "Alice", grades: [90, 85, 88])

let student2 = Student(name: "Bob", grades: [78, 82, 80])

let student3 = Student(name: "Charlie", grades: [95, 92, 89])

let classroom = Classroom(className: "Math 101")

classroom.addStudent(student1)

classroom.addStudent(student2)

classroom.addStudent(student3)

// Display average grades for all students

classroom.displayAverageGrades()