// Zorah Fung, CSE 143
// Examples of references

import java.util.*;

public class ReferenceFun {
    public static void main(String[] args) {
        listMystery();
        studentMystery();
    }

    public static void listMystery() {
        ArrayList<Integer> list = new ArrayList<Integer>();
        ArrayList<Integer> list2 = list;
        ArrayList<Integer> list3 = new ArrayList<Integer>();

        System.out.println("list: " + list);
        System.out.println("list2: " + list2);
        System.out.println("list3: " + list3);
        System.out.println();

        list.add(42);
        System.out.println("list.add(42);");
        System.out.println("list: " + list);
        System.out.println("list2: " + list2);
        System.out.println("list3: " + list3);
        System.out.println();

        list2.add(17);
        System.out.println("list2.add(17);");
        System.out.println("list: " + list);
        System.out.println("list2: " + list2);
        System.out.println("list3: " + list3);
        System.out.println();

        list3.add(6);
        System.out.println("list3.add(6);");
        System.out.println("list: " + list);
        System.out.println("list2: " + list2);
        System.out.println("list3: " + list3);
        System.out.println();

        ArrayList<Integer> list4 = new ArrayList<Integer>();
        list4.add(88);
        list = list4; // Doesn't change list2!
        System.out.println("list4.add(88);");
        System.out.println("list = list4;");
        System.out.println("list: " + list);
        System.out.println("list2: " + list2);
        System.out.println("list3: " + list3);
        System.out.println("list4: " + list4);
        System.out.println();
    }

    public static void studentMystery() {
        Student austin = new Student();
        austin.name = "Austin";
        austin.id = 1;
        austin.grades = new ArrayList<Double>();
        austin.grades.add(2.5);
        austin.grades.add(2.5);
        austin.grades.add(2.5); // [4.0, 4.0, 4.0]

        Student bella = new Student();
        bella.name = "Bella";
        bella.id = 2;
        bella.grades = new ArrayList<Double>();
        bella.grades.add(4.0);
        bella.grades.add(4.0);
        bella.grades.add(4.0); // [4.0, 4.0, 4.0]

        System.out.println("Austin's grades: " + austin.grades);
        System.out.println("Bella's grades: " + bella.grades);
        System.out.println();

        austin.grades = bella.grades;
        setGrades(bella.grades, 0.0);
        System.out.println("Austin's grades: " + austin.grades);
        System.out.println("Bella's grades: " + bella.grades);
        System.out.println();

        bella.grades = new ArrayList<Double>();
        System.out.println("Austin's grades: " + austin.grades);
        System.out.println("Bella's grades: " + bella.grades);
        System.out.println();
    }

    // Given an ArrayList of grades, sets each grade to the given grade
    public static void setGrades(ArrayList<Double> grades, double grade) {
        for (int i = 0; i < grades.size(); i++) {
            grades.set(i, grade);
        }
    }
}