Question

Write you code in a class named HighScores, in file named HighScores.java.

Write a program that records high-score data for a fictitious game. The program will ask the user to enter five names, and five scores. It will store the data in memory, and print it back out sorted by score.

The output from your program should look approximately like this:

Enter the name for score #1: Suzy

Enter the score for score #1: 600

Enter the name for score #2: Kim

Enter the score for score #2: 9900

Enter the name for score #3: Bob

Enter the score for score #3: 1012

Enter the name for score #4: Armando

Enter the score for score #4: 8000

Enter the name for score #5: Tim

Enter the score for score #5: 514

Top Scorers:

Kim: 9900

Armando: 8000

Bob: 1012

Suzy: 600

Tim: 514

Requirements

The data must be stored in two ArrayLists: one ArrayList of strings named names, and one ArrayList of Integers named scores. These ArrayLists must be declared in the main method.

All of the user input should be done in a method named initialize. It should have the following signature:

public static void initialize(ArrayList<String> names, ArrayList<Integer> scores)

You should write a function that sorts both array lists, based on the values in the scores array list. This is one of the more conceptually challenging parts of the assignment. You want to sort the scores array list, and simultaneously alter the names array list so that the names continue to line up with their respective scores by index. In the example data above, when the score 9900 moves to the first element of the scores array list, the name “Kim” should also be moved to the top of the names array list. The function should have the following signature:

public static void sort(ArrayList<String> names, ArrayList<Integer> scores)

Finally you should write a method that displays the contents of the two arraylists. It should have the following signature:

public static void display(ArrayList<String> names, ArrayList<Integer> scores)

The main method should be very short. It should just declare and initialize the two arraylists and then invoke these three methods.

Answer 1

HighScores.java

import java.util.ArrayList;

import java.util.Scanner;

public class HighScores {

public static void main(String[] args) {

ArrayList<String> names = new ArrayList<String>();

ArrayList<Integer> scores = new ArrayList<Integer>();

//reading names and scores

initialize(names, scores);

//sorting the lists based on score.

sort(names, scores);

//displaying the contents of both arrayist

display(names, scores);

}

public static void initialize(ArrayList<String> names, ArrayList<Integer> scores){

Scanner scan = new Scanner(System.in);

for(int i=1; i<=5; i++){

System.out.println("Enter the name for score #"+i+":");

names.add(scan.next());

System.out.println("Enter the score for score #"+i+":");

scores.add(scan.nextInt());

}

}

public static void sort(ArrayList<String> names, ArrayList<Integer> scores){

int n = names.size();

int temp = 0;

String tempStr = "";

for(int i=0; i < n; i++){

for(int j=1; j < (n-i); j++){

//checking max score and sorting based on it.

if(scores.get(j-1) < scores.get(j)){

//swap the elements!

//swapping scores

temp = scores.get(j-1);

scores.set(j-1,scores.get(j));

scores.set(j, temp);

//swapping names

tempStr = names.get(j-1);

names.set(j-1,names.get(j));

names.set(j, tempStr);

}

}

}

}

public static void display(ArrayList<String> names, ArrayList<Integer> scores){

System.out.println("Top Scorers:");

//printing the elements up to the size of both arrays.

for(int i=0; i<names.size(); i++){

System.out.println(names.get(i)+": "+scores.get(i));

}

}

}

Output:

Enter the name for score #1:
Suzy
Enter the score for score #1:
600
Enter the name for score #2:
Kim
Enter the score for score #2:
9900
Enter the name for score #3:
Bob
Enter the score for score #3:
1012
Enter the name for score #4:
Armando
Enter the score for score #4:
8000
Enter the name for score #5:
Tim
Enter the score for score #5:
514
Top Scorers:
Kim: 9900
Armando: 8000
Bob: 1012
Suzy: 600
Tim: 514