# Activities ## S9Problem1.java ```java import java.util.*; public class S9Problem1 { public static void main(String[] args) { System.out.println("Problem 1"); Scanner in = new Scanner(System.in); } } ``` ## S9Problem2.java ```java import java.util.*; public class S9Problem2 { public static void main(String[] args) { System.out.println("Problem 2"); Scanner in = new Scanner(System.in); } } ``` ## S9Problem3.java ```java import java.util.*; public class S9Problem3 { public static void main(String[] args) { System.out.println("Problem 3"); Scanner in = new Scanner(System.in); } } ``` ## S9Problem4.java ```java import java.util.*; public class S9Problem4 { public static void main(String[] args) { System.out.println("Problem 4"); Scanner in = new Scanner(System.in); } } ``` ## S9Problem5.java ```java import java.util.*; public class S9Problem5 { public static void main(String[] args) { System.out.println("Problem 5"); Scanner in = new Scanner(System.in); } } ``` ## S9Problem6.java ```java import java.util.*; public class S9Problem6 { public static void main(String[] args) { System.out.println("Problem 6"); Scanner in = new Scanner(System.in); } } ``` ## S9Problem7.java ```java import java.util.*; public class S9Problem7 { public static void main(String[] args) { System.out.println("Problem 7"); Scanner in = new Scanner(System.in); } } ``` ## S9Problem8.java ```java import java.util.*; public class S9Problem8 { public static void main(String[] args) { System.out.println("Problem 8"); Scanner in = new Scanner(System.in); } } ``` ## S9Problem9.java ```java import java.util.*; public class S9Problem9 { public static void main(String[] args) { System.out.println("Problem 9"); Scanner in = new Scanner(System.in); } } ``` ## S9Problem10.java ```java import java.util.*; public class S9Problem10 { public static void main(String[] args) { System.out.println("Problem 10"); // Rewrite this code to use an ArrayList instead of an array String[] toDoList = new String[3]; toDoList[0] = "Do homework"; toDoList[1] = "Help make dinner"; toDoList[2] = "Call grandma"; // changing element 1 toDoList[1] = "Order pizza"; System.out.println(toDoList.length + " things to do!"); System.out.println("Here's the first thing to do: " + toDoList[0]); // remove item 0 and move everything down // (this can be done in one method call with ArrayList) toDoList[0] = toDoList[1]; toDoList[1] = toDoList[2]; toDoList[2] = ""; System.out.println("Here's the next thing to do: " + toDoList[0]); } } ``` ## GroceryStoreManager.java ```java import java.util.*; public class GroceryStoreManager { // Parallel ArrayLists private static ArrayList itemNames = new ArrayList<>(); private static ArrayList prices = new ArrayList<>(); private static Scanner scanner = new Scanner(System.in); public static void main(String[] args) { // Add some sample data addSampleData(); int choice; do { displayMenu(); choice = scanner.nextInt(); scanner.nextLine(); // consume newline switch (choice) { case 1: addNewItem(); break; case 2: removeItem(); break; case 3: updatePrice(); break; case 4: displayAllItems(); break; case 5: findMostExpensive(); break; case 6: findLeastExpensive(); break; case 7: System.out.println("Goodbye!"); break; default: System.out.println("Invalid choice. Please try again."); } } while (choice != 7); } public static void displayMenu() { System.out.println("\n=== GROCERY STORE INVENTORY ==="); System.out.println("1. Add new item"); System.out.println("2. Remove item"); System.out.println("3. Update price"); System.out.println("4. Display all items"); System.out.println("5. Find most expensive item"); System.out.println("6. Find least expensive item"); System.out.println("7. Exit"); System.out.print("Enter your choice: "); } public static void addSampleData() { itemNames.add("Apples"); prices.add(2.99); itemNames.add("Bread"); prices.add(1.50); itemNames.add("Milk"); prices.add(3.25); itemNames.add("Bananas"); prices.add(1.25); } public static void addNewItem() { System.out.print("Enter item name: "); String name = scanner.nextLine(); System.out.print("Enter price: $"); double price = scanner.nextDouble(); // TODO: Add the item name and price to their respective ArrayLists System.out.println("Item added successfully!"); } public static void removeItem() { displayAllItems(); if (itemNames.size() == 0) { System.out.println("No items to remove!"); return; } System.out.print("Enter the number of the item to remove: "); int index = scanner.nextInt() - 1; // TODO: Check if index is valid (between 0 and size-1) // TODO: Remove item from both ArrayLists at the same index System.out.println("Item removed successfully!"); } public static void updatePrice() { displayAllItems(); if (itemNames.size() == 0) { System.out.println("No items to update!"); return; } System.out.print("Enter the number of the item to update: "); int index = scanner.nextInt() - 1; // TODO: Check if index is valid // TODO: Ask for new price and update the prices ArrayList using .set() System.out.println("Price updated successfully!"); } public static void displayAllItems() { System.out.println("\n=== CURRENT INVENTORY ==="); if (itemNames.size() == 0) { System.out.println("No items in inventory!"); return; } // TODO: Loop through both ArrayLists and display: // Item number, name, and price // Format: "1. Apples - $2.99" } public static void findMostExpensive() { if (prices.size() == 0) { System.out.println("No items in inventory!"); return; } // TODO: Find the index of the item with the highest price // Display the item name and price // Hint: Use a loop to compare prices and track the highest } public static void findLeastExpensive() { if (prices.size() == 0) { System.out.println("No items in inventory!"); return; } // TODO: Find the index of the item with the lowest price // Display the item name and price // Hint: Use a loop to compare prices and track the lowest } } ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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