Activities
S9Problem1.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
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
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
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
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
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
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
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
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
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
import java.util.*;
public class GroceryStoreManager {
// Parallel ArrayLists
private static ArrayList<String> itemNames = new ArrayList<>();
private static ArrayList<Double> 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
}
}Last updated