Simple Sorting Problem, Please Help!

[cookieman]

I am new to the website with a small problem. I know it is probably really simple and I heard you guys could help me.

My objective is to:Computing weekly hours for each employee. Suppose the weekly hours for all employees are stored in a two-dimensional array;
Each row records an employee's 7 day work hours with seven
columns. I need to write a program that displays employee numbers (0-7) and their work hours in DECREASING order of work hours (use the sort of your choice. Store the total work hours into a second one-dimensional array, and sort the second array. You could use a third array storing "employee #" and swap it when you swap the array containing total hours worked.

So far my code is:

public class HW5b
{
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}};


for(int i = 0; i < hours.length; i++)
{
int totalHours = 0;

for(int n = 0; n < hours[i].length; n++)
{
totalHours += hours[i][n];
}

swapEmployeeMethod(hours, totalHours);

System.out.println("Employee " + i + "'s hours are " + totalHours);

}

}

public static void swapEmployeeMethod(int[][] hours, int totalHours)
{
//I need to figure out how to swap the suckers here

}
}

I am sure this is a piece of cake for one of you and I would appreciate some pointers as a newbie to Java. Thanks!

[nspils]

It depends on the data structure you choose to use to store the combination of employee number and total hours worked. Could be as easy as another 2D array, 7 x 2, holding the data ... each row would be a pair, and you can sort (rows) based upon the value of total hours worked.

You can also use other structures, especially those which allow you to treat paired values as a single unit ...

[sjalle]

This one sorts both ways.

/**
 * Bubblesort algorithm
 * @author sjalle
 * @version 1.0
 */

public class BubbleSort {
  public final static int ASCENDING=0;
  public final static int DESCENDING=1;
  private int [] values;
  private int sortDirection=ASCENDING;
  public BubbleSort(int [] values, int sortDirection) {
    this.values=values;
    this.sortDirection=sortDirection;
  }
  public void sort() {
    boolean wasSwapped;
    for (int i=values.length-1;i>=0; i--) {
      wasSwapped=false;
      for (int j=0;j<i;j++) {
        if (swap(j)) wasSwapped=true;
      }
      /**
       * if a scan completes without any swapping the array is sorted
       */
      if (!wasSwapped) break;
    }
  }

  private boolean swap(int pos) {
    if ( (this.sortDirection==ASCENDING && values[pos] > values[pos+1]) ||
         (this.sortDirection==DESCENDING && values[pos] < values[pos+1])) {
      int copy=values[pos];
      values[pos]=values[pos+1];
      values[pos+1]=copy;
      return true;
    } else {
      return false;
    }
  }
  public static void main(String[] args) {
    int [] v=new int[] {
        2,4,3,5,4,6,7,5,3,1,33,44,22
    };
    BubbleSort bs=null;
    System.out.println("Unsorted:");
    listValues(v);
    bs = new BubbleSort(v, BubbleSort.DESCENDING);
    bs.sort();
    System.out.println("Sorted Decending:");
    listValues(v);
    bs = new BubbleSort(v, BubbleSort.ASCENDING);
    bs.sort();
    System.out.println("Sorted Ascending:");
    listValues(v);
  }
  static void listValues(int [] v) {
    for (int i=0;i<v.length;i++) {
      System.out.println(v[i]);
    }

  }
}