Question

JAVA

In this PoD you will use an ArrayList to store different pet names (there are no repeats in this list). This PoD can be done in your demo program (where your main method is) – you don’t have to create a separate class for today.

Details

Create an arraylist of Strings, then using a Scanner object you will first read in a number that will tell you how many pet names (one word) you will add to the arraylist.

Once you have added all the names, print the list.

Then read in one more pet name. If this is pet name already exists, do nothing, but if the pet name isn’t in the list, add it to the front of the list (e.g., the first position).

Print the list again.

Next read in two more pet names. If the first pet name is in the list, replace it with the second pet name. If the first pet name isn’t in the list, add the second pet name to the end of the list.

Print the list again.

Input

Example Input:
5 Whiskers Benji Lassie Smokey Bob Triffy Bob Max

Output

Example Output:
[Muffin, Benji, Snowball, Fluffy]
[Muffin, Benji, Snowball, Fluffy]
[Muffin, Benji, Snowball, Whiskers, Fluffy]

Answer 1

//import required library files
import java.util.ArrayList;
import java.util.*;

//class definition
public class petNames {
//main function definition
public static void main(String[] args) {
   
    //Create the arraylist
    ArrayList<String> petNames = new ArrayList<String>();
   
    //create scanner object to take user input
    Scanner sc = new Scanner(System.in);
   
    //prompt user to enter number of pet names and store in count
    System.out.print("How many pet names to enter? ");
    int count = sc.nextInt();
   
    //Take user input for petnames and store in arraylist
   
    System.out.println("Enter "+count+" pet names");
    String str="";
    for(int i=0;i<count;i++){
      str=sc.next();
      petNames.add(str);
    }
   
    //print the list
    System.out.println(petNames);
   
    //Prompt user to enter one more pet name
    System.out.println("Enter one more pet name");
   
    String pet = sc.next();
   
    //If pet name not present in arraylist add at index 0
    if(!petNames.contains(pet)){
      petNames.add(0,pet);
    }
   
    //print the list
    System.out.println(petNames);
   
    //prompt user to enter two more pet names
    System.out.println("Enter two more pet names");
   
    //Store user input in two variables
    String pet1,pet2;
   
    pet1=sc.next();
    pet2=sc.next();
   
    //If the first pet name is in the list, replace it with the second pet name.
    // If the first pet name isn’t in the list, add the second pet name to the end of the list.
   
    if(petNames.contains(pet1))
    {
      int index = petNames.indexOf(pet1);
      petNames.remove(index);
      petNames.add(index,pet2);
    }
    else {
      petNames.add(pet2);
    }
   
    //Print the list
    System.out.println(petNames);
   
}

}