Question

Java. I have class ScoreBoard that holds a 2d array of each player's score. COde Bellow

Example:

	Score 1	score 2
Player1	20	21
Player2	15	32
Player3	6	7

Using the method ScoreIterator so that it returns anonymous object of type ScoreIterator , iterate over all the scores, one by one. Use the next() and hasNext()

public interface ScoreIterator {
    int next();
    boolean hasNext();

Class ScoreBoard :

import java.util.*;

public class ScoreBoard {
    int[][] scores ;

    public ScoreBoard (int numOfPlayers, int numOfRounds) {
        scores = new int[numOfPlayers][numOfRounds];
        Random rand = new Random();
        for (int i = 0; i < numOfPlayers; i++) {
            for (int j = 0; j < numOfRounds; j++) {
                scores [i][j] = 50 + rand.nextInt(51);
            }
        }
    }

    public ScoreIterator scoreIterator () {
        // return anonymous object of type ScoreIterator 

        
    }

    public static void main(String[] args) {
        ScoreBoard sb = new ScoreBoard (3, 2);
        ScoreIterator iterator = sb.ScoreIterator ();
        while (iterator.hasNext()) {
            System.out.println(iterator.next());
        }
    }
}

}

Answer 1

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CODE TO COPY

ScoreBoard.java

import java.util.*;

public class ScoreBoard {
   int[][] scores;

   public ScoreBoard(int numOfPlayers, int numOfRounds) {
       scores = new int[numOfPlayers][numOfRounds];
       Random rand = new Random();
       for (int i = 0; i < numOfPlayers; i++) {
           for (int j = 0; j < numOfRounds; j++) {
               scores[i][j] = 50 + rand.nextInt(51);
           }
       }
   }

   public ScoreIterator scoreIterator() {
       ScoreIterator si = new ScoreIterator() {

           private int row = 0;
           private int col = 0;

           @Override
           public int next() {
               if (hasNext()) {
                   while (row < scores.length) {
                       while (col < scores[0].length) {

                           int x = scores[row][col];
                           col++;
                           if (col == scores[0].length) {
                               col = 0;
                               row++;
                           }
                           return x;
                       }
                       row++;
                   }
               }
               return 0;
           }

           @Override
           public boolean hasNext() {
               return row < scores.length && col < scores[0].length;
           }
       };

       return si;
   }

   public static void main(String[] args) {
       ScoreBoard sb = new ScoreBoard(3, 2);

       System.out.println("using for loop");
       for (int i = 0; i < sb.scores.length; i++) {
           for (int j = 0; j < sb.scores[0].length; j++) {
               System.out.println(sb.scores[i][j]);
           }
       }

       System.out.println("----------------");
       System.out.println("using iterator");

       ScoreIterator iterator = sb.scoreIterator();
       while (iterator.hasNext()) {
           System.out.println(iterator.next());
       }
   }

}

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ScoreIterator.java

public interface ScoreIterator {
    int next();
    boolean hasNext();
}

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EXPLANATION

import java.util.*; // for using random class

public class ScoreBoard { // creating a class names ScoreBoard
   int[][] scores; // to store numbers in 2d array

   public ScoreBoard(int numOfPlayers, int numOfRounds) { //constructor to intialize scores
       scores = new int[numOfPlayers][numOfRounds];
       Random rand = new Random(); // creating a random object rand
       for (int i = 0; i < numOfPlayers; i++) { // for loop for rows
           for (int j = 0; j < numOfRounds; j++) { // for loop for each element in row
               scores[i][j] = 50 + rand.nextInt(51); // generating a random number
           }
       }
   }

   public ScoreIterator scoreIterator() { // creating a scoreiterator method which returns ScoreIterator object anonymously
       ScoreIterator si = new ScoreIterator() { //creating a ScoreIterator object si

           private int row = 0; // set row as 0
           private int col = 0; // set col as 0

           @Override
           public int next() { // to return next element
               if (hasNext()) { // if the scores array has elements
                   while (row < scores.length) { // then check if the row is not at the end
                       while (col < scores[0].length) { // check if the column is not at the end

                           int x = scores[row][col]; // get the element at the position
                           col++; // increase column by 1
                           if (col == scores[0].length) { // if element is at the end of the row
                               col = 0; // set col as 0
                               row++; // increase row by 1
                           }
                           return x; // return the number
                       }
                       row++; // increase the row number after each element is returned, in order to return the number
                   }
               }
               return 0; // return 0 if no number is found
           }

           @Override
           public boolean hasNext() {
               return row < scores.length && col < scores[0].length; // check if the row and col are inside the range
           }
       };

       return si; //return the object
   }

   public static void main(String[] args) {
       ScoreBoard sb = new ScoreBoard(3, 2);

//remove these lines and for loop if needed, this was only to check the elements and show you

       System.out.println("using for loop"); // printing statement
       for (int i = 0; i < sb.scores.length; i++) { // for loop for row
           for (int j = 0; j < sb.scores[0].length; j++) { // for loop for each element in row
               System.out.println(sb.scores[i][j]); // print the element
           }
       }

       System.out.println("----------------"); // printing line
       System.out.println("using iterator"); // printing statement

       ScoreIterator iterator = sb.scoreIterator(); // creating a iterator using the method which return the object anonymously
       while (iterator.hasNext()) { // while loop to check if element exsists
           System.out.println(iterator.next()); // printing the element
       }
   }

}

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OUTPUT

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IF YOU HAVE ANY DOUBTS REGARDING THE SOLUTION PLEASE COMMENT BELOW I WILL HELP YOU

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