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Thread: Selection sort not working

  1. #1
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    Default Selection sort not working

    I can not figure out what is wrong with my code I have looked over it many times and cant find anything wrong with it. When I run the program it doesn't sort the list by the Item Id.

    this is my tester class
    import java.util.*;

    public class Tester
    {
    public static void printInvetory(List<Item> a)
    {
    System.out.println("ItemID ItemName InStoreID Price");
    System.out.println("-------------------------------------------");
    for(int i = 0; i < a.size(); i++)
    {
    System.out.println(a.get(i));
    }
    }

    public static void sortID(List<Item> a)
    {
    int i;
    int k;
    int posmax;
    Item temp;
    for(i = a.size() - 1; i >= 0; i--)
    {
    posmax = 0;
    for(k = 0 ; k <= i ; k++)
    {
    if(a.get(k).getItemID() > a.get(posmax).getItemID())
    posmax = k;
    }
    temp = a.get(i);
    a.set(i, a.get(posmax));
    a.set(posmax, temp);
    }
    }

    public static void main(String[] args)
    {
    List<Item> myStore = new ArrayList<Item>();

    myStore.add(new Item(0004, 200, 10.5, "Air Filters"));
    myStore.add(new Item(0002, 60, 21.5, "Door Knobs"));
    myStore.add(new Item(0006, 90, 9.99, "Hammers "));
    myStore.add(new Item(0001, 80, 19.99, "Levels "));
    myStore.add(new Item(0005, 100, 59, "Ceiling fans"));
    myStore.add(new Item(0003, 55, 80, "Wrench Sets"));

    printInvetory(myStore);
    System.out.println();
    printInvetory(myStore);
    }
    }

    this is my constructor class
    public class Item
    {
    private int itemID;
    private int inStore;
    private double Price;
    private String itemName;

    public Item(int id, int is, double p, String in)
    {
    itemID = id;
    inStore = is;
    Price = p;
    itemName = in;
    }

    public String getName()
    {
    return itemName;
    }

    public int getItemID()
    {
    return itemID;
    }

    public int getInStore()
    {
    return inStore;
    }

    public double getPrice()
    {
    return Price;
    }

    public String toString()
    {
    return itemID + "\t" + itemName + "\t" + inStore + "\t" + "$ " + Price;
    }
    }

    PLZ HELP.


  2. #2
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    Default Re: Selection sort not working

    When posting code, please use the highlight tags to preserve formatting.

    You're going to have to debug your code to figure out where its execution differs from your expectations. Recommended reading: http://www.javaprogrammingforums.com...t-println.html
    Useful links: How to Ask Questions the Smart Way | Use Code Tags | Java Tutorials
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  3. #3
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    Default Re: Selection sort not working

    Your sortID method is never called... main method should look like this (assuming you only want to print the list once)...
    public static void main(String[] args) {
    	List<Item> myStore = new ArrayList<Item>();
     
    	myStore.add(new Item(0004, 200, 10.5, "Air Filters"));
    	myStore.add(new Item(0002, 60, 21.5, "Door Knobs"));
    	myStore.add(new Item(0006, 90, 9.99, "Hammers "));
    	myStore.add(new Item(0001, 80, 19.99, "Levels "));
    	myStore.add(new Item(0005, 100, 59, "Ceiling fans"));
    	myStore.add(new Item(0003, 55, 80, "Wrench Sets"));
     
    	sortID(myStore);
    	printInvetory(myStore);
    	System.out.println();
        }


    All intelligent thoughts have already been thought;
    what is necessary is only to try to think them again.



  4. #4
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    Default Re: Selection sort not working

    I am gonna print it every time I sort it.

  5. #5
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    Default Re: Selection sort not working

    Wow I just looked back a noticed I never called the method ...... I feel Kinda dumb but thanks for the help.

  6. #6
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    Default Re: Selection sort not working

    Quote Originally Posted by killer3p0 View Post
    Wow I just looked back a noticed I never called the method ...... I feel Kinda dumb but thanks for the help.
    We all have those kinds of days...


    All intelligent thoughts have already been thought;
    what is necessary is only to try to think them again.



  7. The Following User Says Thank You to WhiteSoup12 For This Useful Post:

    killer3p0 (May 16th, 2012)

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