SortingComparator.java

import java.util.*;

class Player {
	String name;
	int score;

	Player(String name, int score) {
		this.name = name;
		this.score = score;
	}
}

class Checker implements Comparator<Player> {
  	// complete this method
	public int compare(Player a, Player b) {
        // compare scores of a and b in DESCENDING order
        if (a.score < b.score)
            return 1;
        else if (a.score > b.score)
            return -1;
        else {//in case scores are equal
            //compare names of a and b in ASCENDING order
            int minLength = Math.min(a.name.length(), b.name.length());
            for (int i=0; i < minLength; i++) {
                //compare in common string length
                int aChar = Character.getNumericValue(a.name.charAt(i));
                int bChar = Character.getNumericValue(b.name.charAt(i));
                if (aChar < bChar)
                    return -1;
                else if (aChar > bChar)
                    return 1;
                else
                    continue;
            }
            //if the code runs to HERE without return,
            //eg. [bb, 20] and [bbb, 20]
            //then compare string lengths for decision
            if (a.name.length() < b.name.length())
                return -1;
            else if (a.name.length() > b.name.length())
                return 1;
            else
                return 0;
        }
    }
}


public class Solution {

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int n = scan.nextInt();

        Player[] player = new Player[n];
        Checker checker = new Checker();
        
        for(int i = 0; i < n; i++){
            player[i] = new Player(scan.next(), scan.nextInt());
        }
        scan.close();

        Arrays.sort(player, checker);
        for(int i = 0; i < player.length; i++){
            System.out.printf("%s %s\n", player[i].name, player[i].score);
        }
    }
}

SortingComparator.txt

Comparators are used to compare two objects. In this challenge, you'll create a comparator and use it to sort an array. The Player class is provided in the editor below. It has two fields:

1. name: a string.
2. score: an integer.
Given an array of n Player objects, write a comparator that sorts them in order of decreasing score. If 2 or more players have the same score, sort those players alphabetically ascending by name. To do this, you must create a Checker class that implements the Comparator interface, then write an int compare(Player a, Player b) method implementing the Comparator.compare(T o1, T o2) method. In short, when sorting in ascending order, a comparator function returns -1 if a<b, 1 if a>b, and 0 if a=b.

For example, given n = 3 Player objects with Player.name, Player.score values of 
data = [Smith,20],[Jones,15],[Jones,20], we want to sort the list as 
data_sorted = [Jones,20],[Smith,20],[Jones,15].

Function Description

Declare a Checker class that implements the comparator method as described. It should sort first descending by score, then ascending by name. The code stub reads the input, creates a list of Player objects, uses your method to sort the data, and prints it out properly.