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changing my code to add a loop to put in values

jerry-2112 asked
Last Modified: 2012-08-24
I have a code here that works fine, but I was wondering how to change it to use a loop to put in my array vaules.  This was fairly easy todo because there was only 20 total vaules to add but larger program would need some sort of loop.  Here is my working Code
import java.util.ArrayList;

public class ThreeArrayLists {

    public static void main(String[] args) {
        ArrayList priceList = new ArrayList();
        ArrayList quantityList = new ArrayList();
        ArrayList amountList = new ArrayList();
        //PRICE lIST
        priceList.add(new Double(10.62));
        priceList.add(new Double(14.89));
        priceList.add(new Double(13.21));
        priceList.add(new Double(16.55));
        priceList.add(new Double(18.62));
        priceList.add(new Double(9.47));
        priceList.add(new Double(6.58));
        priceList.add(new Double(18.32));
        priceList.add(new Double(12.15));
        priceList.add(new Double(3.98));
        //QUANTITY LIST   
        quantityList.add(new Double(4.0));
        quantityList.add(new Double(8.5));
        quantityList.add(new Double(6.0));
        quantityList.add(new Double(7.35));
        quantityList.add(new Double(9.0));
        quantityList.add(new Double(15.3));
        quantityList.add(new Double(3));
        quantityList.add(new Double(5.4));
        quantityList.add(new Double(2.9));
        quantityList.add(new Double(4.8));
       // call extend method
        extend(amountList, quantityList, priceList);
        //call display method
        display(quantityList, priceList, amountList);

// display method
    private static void display(ArrayList quantityList, ArrayList priceList, ArrayList amountList)  {
          //for loop to display arrays
        for (int i = 0; i < 10; i++) {
        //format using %.2f to round all numbers to 2 decimals
            System.out.format("%d)  %.2f * %.2f = %.2f \n",i+1, 
Double.valueOf(quantityList.get(i).toString()), Double.valueOf(amountList.get(i).toString()));

    private static void extend(ArrayList amountList, ArrayList quantityList, ArrayList priceList) {
           //for loop to do the math
        for (int i = 0; i < 10; i++) {
            amountList.add((Double.valueOf(priceList.get(i).toString())) * (Double.valueOf(quantityList.get(i).toString())));



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Here is the sort of loop I'd like to add.

for i = 0 to i < 10

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So would my Array totals look like this :
final double[] PRICE_ARRAY = { 10.62, 14.89, 13.21, 16.55, 18.62, 9.47,
            6.58, 18.32, 12.15, 3.98 };
    final double[] QUANTITY_ARRAY = { 4.0, 8.5, 6.0, 7.35, 9.0, 15.3, 3.0, 5.4,
            2.9, 4.8 };

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Is this a simple change or hardcore ?  What I have is good for my assignment, just wondering.  Thanks Jerry
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