completed derusting

src/ArrayPractice.java

@@ -1,17 +1,37 @@
 public class ArrayPractice {
-  public static void main(String[] args) {
+  public static void main(String[] args) 
+  {
     // Create an array of Strings of size 4
+    String[] array = new String[4]; 
 
     // Set the value of the array at each index to be a different String
+    array[0] = "Honda";
+    array[1] = "Ford";
+    array[2] = "Toyota";
+    array[3] = "Chevy";
+
     // It's OK to do this one-by-one
 
+
     // Get the value of the array at index 2
+    String value = array[2];
+    System.out.println(value);
 
     // Get the length of the array
+    int arrayLength = array.length;
+    System.out.println(arrayLength);
 
     // Iterate over the array using a traditional for loop and print out each item
 
+    for(int i = 0; i < array.length; i++)
+      System.out.println(array[i]);
+
+
     // Iterate over the array using a for-each loop and print out each item
+    for(String cars : array)
+    {
+      System.out.println(cars);
+    }
 
     /*
      * Reminder!
@@ -20,3 +40,5 @@ public static void main(String[] args) {
      */
   }
 }
+//compiling is javac src/"filename"
+//running is -cp src "Name of file"

src/ListPractice.java

@@ -1,28 +1,66 @@
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+
+
 public class ListPractice {
 
 
-  public static void main(String[] args) {
+  public static void main(String[] args) 
+  {
     // Create an empty ArrayList of Strings and assign it to a variable of type List
+    List<String> cars = new ArrayList<>();
 
     // Add 3 elements to the list (OK to do one-by-one)
+    cars.add("Honda");
+    cars.add("Toyota");
+    cars.add("Chevy");
 
     // Print the element at index 1
+    System.out.println(cars.get(1));
+
 
     // Replace the element at index 1 with a new value
+    cars.set(1, "Tesla"); //integer for the index and string 
+    System.out.println(cars.get(1));
+
+
     // (Do not insert a new value. The length of the list should not change)
 
+
     // Insert a new element at index 0 (the length of the list will change)
+    cars.add(0, "BMW"); 
+    System.out.println(cars.get(0));
 
     // Check whether the list contains a certain string
+    boolean containsCars = cars.contains("BMW");
+    System.out.println(containsCars);
 
     // Iterate over the list using a traditional for-loop.
+    for (int i = 0; i < cars.size(); i++)
+    System.out.println(cars.get(i));
+
     // Print each index and value on a separate line
+     for (int i = 0; i < cars.size(); i++)
+    System.out.println(i + cars.get(i));
 
     // Sort the list using the Collections library
+    Collections.sort(cars);
+    System.out.println(cars);
 
     // Iterate over the list using a for-each loop
+
+    for(String cars1: cars)
+    {
+      System.out.println();
+       System.out.println(cars1);
+    }
+
+
     // Print each value on a second line
 
+
     /*
      * Usage tip!
      * 

src/MapPractice.java

@@ -1,28 +1,64 @@
-
+import java.util.HashMap;
+import java.util.Map;
 
 public class MapPractice {
-  public static void main(String[] args) {
+  public static void main(String[] args) 
+  {
     // Create a HashMap with String keys and Integer values and
+      Map<String, Integer> carMap = new HashMap<>(); 
+
+
     // assign it to a variable of type Map
+
+
 
     // Put 3 different key/value pairs in the Map
     // (it's OK to do this one-by-one)
+    carMap.put("Honda", 1);
+    carMap.put("Ford", 2);
+    carMap.put("Chevy", 3);
+    carMap.put("Lexus", 4);
 
     // Get the value associated with a given key in the Map
+    int car = carMap.get("Honda");
+    System.out.println(car);
 
     // Find the size (number of key/value pairs) of the Map
+      int car1 = carMap.size();
+      System.out.println(car1);
+
 
     // Replace the value associated with a given key (the size of the Map shoukld not change)
+    carMap.put("Honda", 3);
+    System.out.println(carMap.get("Honda"));
 
     // Check whether the Map contains a given key
+    boolean containsCar = carMap.containsKey("Honda");
+    System.out.println(containsCar);
 
     // Check whether the Map contains a given value
+    boolean containsValue1 = carMap.containsValue(2);
+    System.out.println(containsValue1);
+
 
     // Iterate over the keys of the Map, printing each key
+    for (String key : carMap.keySet())
+    {
+      System.out.println(key);
+    }
 
     // Iterate over the values of the map, printing each value
+    for (Integer value : carMap.values())
+    {
+      System.out.println(value);
+    }
 
     // Iterate over the entries in the map, printing each key and value
+    for(String key : carMap.keySet())
+    {
+      System.out.println(key + " " + carMap.get(key));
+    }
+
 
     /*
      * Usage tip!

src/NumberPractice.java

@@ -1,17 +1,37 @@
-public class NumberPractice {
-  public static void main(String args[]) {
+public class NumberPractice 
+{
+  public static void main(String args[]) 
+  {
     // Create a float with a negative value and assign it to a variable
+    float negativeValue = -1.0f;
+    System.out.println(negativeValue);
 
     // Create an int with a positive value and assign it to a variable
+    int value = 2;
+    System.out.println(value);
 
     // Use the modulo % operator to find the remainder when the int is divided by 3
+    int mod = value % 3;
+    System.out.println(mod);
 
+    if (value % 2 == 0)
+    {
+      System.out.println(value + "is even");
+    }
+    else
+    {
+      System.out.println(value + "is odd");
+    }
+
     // Use the modulo % operator to determine whether the number is even
     // (A number is even if it has a remainder of zero when divided by 2)
     // Use an if-else to print "Even" if the number is even and "Odd"
     // if the number is odd.
 
     // Divide the number by another number using integer division
+    int number = value / 2;
+    System.out.println(number);
+
 
     /*
      * Reminder!

src/Person.java

@@ -3,19 +3,37 @@
  * the Person class.
  */
 
-public class Person {
+public class Person 
+{
   // Declare a public String instance variable for the name of the person
-  // Declare a private int instance variable for the age of the person
+    public String name;
+
 
+  // Declare a private int instance variable for the age of the person
+    private int age;
 
   // Create a constructor that takes the name and age of the person
+  public Person(String name, int age) //parametized constructor
+  {
+    this.name = name;
+    this.age = age;
+  }
+
   // and assigns it to the instance variables
 
 
   // Create a toString method that gives the name and age of the person
+  public String toString()
+  {
+    return name + " " + age;
+  }
 
 
   // Implement the below public instance method "birthYear"
+
+
+
+
   // There should NOT be any print statement in this method.
   /**
    * birthYear returns the year the person was born.
@@ -28,25 +46,37 @@ public class Person {
    * @return The year the person was born
    */
   // (create the instance method here)
+  public int birthYear(int currentYear)
+    {
+        return currentYear - age;
+    }
 
 
   public static void main(String[] args) {
     // Create an instance of Person
+    Person player1 = new Person("Ash", 21);
 
     // Create another instance of Person with a different name and age and
     // assign it to a different variable
+    Person player2 = new Person("Brock", 22);
+
 
     // Print the first person
+    System.out.println(player1);
 
     // Print the second person
+    System.out.println(player2);
 
     // Get the name of the first person and store it in a local variable
+    String mainCharacter = player1.name;
 
     // Using the birthYear method, get the birth year of the first person
+    int DOB = player1.birthYear(2025);
     // and store it in a local variable. Input the actual current year (e.g. 2025)
     // as the argument.
 
     // In a separate statement, print the local variable holding the birth year.
+    System.out.println(DOB);
 
     /**
      * Terminology!

src/SetPractice.java

@@ -1,17 +1,36 @@
+import java.util.HashSet;
+import java.util.Set;
+
+
+
 public class SetPractice {
-  public static void main(String[] args) {
+  public static void main(String[] args) 
+  {
     // Create a HashSet of Strings and assign it to a variable of type Set
+    Set<String> player = new HashSet<>();
 
     // Add 3 elements to the set
     // (It's OK to do it one-by-one)
+    player.add("Ash");
+    player.add("Brock");
+    player.add("Misty");
 
     // Check whether the Set contains a given String
+    boolean containsAsh = player.contains("Ash");
+    System.out.println(containsAsh);
 
     // Remove an element from the Set
+    player.remove("Brock");
 
     // Get the size of the Set
+    int playerSize = player.size();
+    System.out.println(playerSize);
 
     // Iterate over the elements of the Set, printing each one on a separate line
+    for(String elements : player)
+    {
+      System.out.println(elements);
+    }
 
     /*
      * Warning!

src/StringPractice.java

@@ -1,25 +1,53 @@
+import java.util.ArrayList;
+import java.util.List;
+
+
 public class StringPractice {
   public static void main(String[] args) {
     // Create a string with at least 5 characters and assign it to a variable
+    String cars = "Honda";
+
+
 
     // Find the length of the string
+    int carLength = cars.length();
+    System.out.println(carLength);
 
     // Concatenate (add) two strings together and reassign the result
+    cars = cars + "Accord";
+    System.out.println(cars);
 
     // Find the value of the character at index 3
+    char vehicle = cars.charAt(3);
+    System.out.println(vehicle);
 
     // Check whether the string contains a given substring (i.e. does the string have "abc" in it?)
+      boolean containsCars = cars.contains("Civic");
+      System.out.println(containsCars);
+
 
     // Iterate over the characters of the string, printing each one on a separate line
+    for (int i = 0; i < cars.length(); i++)
+    {
+      System.out.println(cars.charAt(i));
+    }
 
     // Create an ArrayList of Strings and assign it to a variable
+    List<String> carList = new ArrayList<>();
 
     // Add multiple strings to the List (OK to do one-by-one)
+    carList.add("Lexus");
+     carList.add("BMW");
+      carList.add("Tesla");
 
     // Join all of the strings in the list together into a single string separated by commas
     // Use a built-in method to achieve this instead of using a loop
+    String carString = carList.toString(); 
+     System.out.println(carString);
 
     // Check whether two strings are equal
+    boolean carEqual = cars.equals("Accord");
+     System.out.println(carEqual);
 
     /*
      * Reminder!