Problem

Write a program create a simple grocery list. Prompt the user for the number of items in the list. Use parallel arrays to store the item names and quantities. Then print the list of items and a count of the number of items

Example Output

Grocery List
------------
1 bacon
12 eggs
4 apples

17 items

More with Arrays

Solution

First, prompt the user for the number of items:

String input;        //temp variable for dialog input	
int    listSize = 0; //the number of items for the grocery list, default 0

input = JOptionPane.showInputDialog("Input length:");
listSize = Integer.parseInt(input);

Now that we have the number of items, listSize, we need to get the items and quantities.

//Create arrays for list items and quantity
String[] groceryList     = new String[listSize];
int[]    groceryQuantity = new int[listSize];

//prompt for input listSize times
for( int i = 0; i < groceryList.length; i++ )
{
	//get the name of the item and 
	groceryList[ i ] = JOptionPane.showInputDialog("Item name");

	input = JOptionPane.showInputDialog("How many " + groceryList[ i ] + "?" );
	groceryQuantity[ i ] = Integer.parseInt( input );
	
}

Last step is to print the list out. We will use the loop for printing to sum the quantities.

int itemCount = 0; //sum of the quantities of the items

//Print a header for the list
System.out.println( "\n\nGrocery List" );
System.out.println( "------------" );

//loop through and print out the list items
for( int i = 0; i < groceryList.length; i++ )
{
	System.out.println( groceryQuantity[ i ] + " " + groceryList[ i ] );
	itemCount = itemCount + groceryQuantity[ i ];
}

System.out.println( "\n" + itemCount + " items.");

Code

Solution Code

import javax.swing.JOptionPane;

public class grovery {
	public static void main( String[] args )
	{

		String input;        //temp variable for dialog input	
		int    listSize = 0; //the number of items for the grocery list, default 0
		
		input = JOptionPane.showInputDialog("Input length:");
		listSize = Integer.parseInt(input);
		
			
		//Create arrays for list items and quantity
		String[] groceryList     = new String[listSize];
		int[]    groceryQuantity = new int[listSize];
		
		//
		for( int i = 0; i < groceryList.length; i++ )
		{
			//get the name of the item and 
			groceryList[ i ] = JOptionPane.showInputDialog("Item name");
		
			input = JOptionPane.showInputDialog("How many " + groceryList[ i ] + "?" );
			groceryQuantity[ i ] = Integer.parseInt( input );
			
		}
		
		int itemCount = 0; //sum of the quantities of the items
		
		//Print a header for the list
		System.out.println( "\n\nGrocery List" );
		System.out.println( "------------" );
		
		//loop through and print out the list items
		for( int i = 0; i < groceryList.length; i++ )
		{
			System.out.println( groceryQuantity[ i ] + " " + groceryList[ i ] );
			itemCount = itemCount + groceryQuantity[ i ];
		}
		
		System.out.println( "\n" + itemCount + " items.");
		
	}
}