How to track index of unsorted array after sorting that array?

1 
import java.util.*;

public class Example {
    public static void main(String[] args) {
        int[][] hours = {
                {2, 4, 3, 4, 5, 8, 8},
                {7, 3, 4, 3, 3, 4, 4},
                {3, 3, 4, 3, 3, 2, 2},
                {9, 3, 4, 7, 3, 4, 1},
                {3, 5, 4, 3, 6, 3, 8},
                {3, 4, 4, 6, 3, 4, 4},
                {3, 7, 4, 8, 3, 8, 4},
                {6, 3, 5, 9, 2, 7, 9}
        };
        int[] weeklyHrs = new int[hours.length];
        for (int i = 0; i < hours.length; i++) {
            for (int j = 0; j < hours[i].length; j++) {
                weeklyHrs[i] = weeklyHrs[i] + hours[i][j];
            }
        }
        for (int i = 0; i < weeklyHrs.length; i++) {
            System.out.print("Employee" + i + ":" + weeklyHrs[i]);
            System.out.println();
        }
        System.out.println();
        int[][] wHTwoD = new int[8][2];
        for (int i = 0; i < 8; i++) {
            for (int j = 0; j < 2; j++) {
                if (j % 2 == 0) {
                    wHTwoD[i][j] = i;
                } else {
                    wHTwoD[i][j] = weeklyHrs[i];
                }
            }
        }

        for (int i = 0; i < 8; i++) {
            for (int j = 0; j < 2; j++) {
                System.out.print(wHTwoD[i][j]);
            }
            System.out.println();
        }

        for (int i = 0; i < weeklyHrs.length; i++) {
            System.out.print(weeklyHrs[i] + " ");
        }
    }

    public static void sort(int[] arr) {
        int temp;
        for (int i = 0; i < arr.length; i++) {
            for (int j = i; j < arr.length; j++) {
                if (arr[j] < arr[i]) {
                    temp = arr[i];
                    arr[i] = arr[j];
                    arr[j] = temp;
                }
            }
        }
    }
}

Question

Suppose the weekly hours for all employees are stored in a two-dimensional array. Each row records an employee’s seven-day work hours with seven columns. For example, the following array stores the work hours for eight employees. Write a program that displays employees and their total hours in increasing order of the total hours.

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I got the total weekly hours of each employees in a 1d array like this

        int[] weeklyHrs = new int[hours.length];  
        for (int i = 0; i < hours.length; i++) {  
            for (int j = 0; j < hours[i].length; j++) {  
                weeklyHrs[i] = weeklyHrs[i] + hours[i][j];  
            }  
        }

However, now I need to sort it and I need to track the index of unsorted array even after sorting it. So far, the book hasn’t started on how to sort 2d array. So I am not going to use this as I take this as a kind of drill.

My concern is simple: How do I track the index of unsorted array after sorting that array?

1 Like
2

So to track the index of the unsorted array store the total hours and original index in a 2d array before you do the sorting that way you can keep track of the index. So now sorting the array on total hours original index will use the ones associated with the correct values and this way you can track the index. Let me know if you still need any help.