import java.util.*;
public class Receipt {
          /* Prints a receipt for Mega Store with discount etc. */


/* Instance Variables  */

Vector items;
Vector prices;
Vector quantities;

/*
	Program description.
*/
	public static void main(String args[]) {
	/* Program statements go here. */
	Receipt myReceipt=new Receipt();
	
	System.out.println("Welcome to the Mega Store");		
	myReceipt.receive();
	myReceipt.sort();
	myReceipt.print();
	}
	
	public Receipt(){
		items=new Vector();
    	prices=new Vector();
    	quantities=new Vector();
	}
	public void receive() {
		String item=" ";
		Float price;
		Integer quantity;
		
		while (!item.equals("")) {
	   		System.out.print("Please enter Item: ");
   			item=Keyboard.in.readString();		
	   		if (!item.equals("")) {
	   			this.items.addElement(item);		
	   			System.out.print("Please enter price: ");
	   			price=Keyboard.in.readFloat();
	   			this.prices.addElement(price);		
	   			System.out.print("Please enter quantity: ");		
	   			quantity=Keyboard.in.readInteger();
				this.quantities.addElement(quantity);
			}
        }
	}
	public void sort() {
	int i;
	int largeIndex;
		for (i=0; i< this.items.size(); i++) {
			largeIndex = this.getLargest(i);
			this.exchange(i, largeIndex);
		}
	}
	
	private int getLargest(int index){
	int		largestIndex;
	int		i;
	Float price1, price2;
	
		largestIndex = index;
		for (i = index + 1; i < this.prices.size(); i++){
			price1=(Float)this.prices.elementAt(i);
			price2=(Float)this.prices.elementAt(largestIndex);
			if (price1.floatValue() > price2.floatValue())
				largestIndex = i;
		}		
		return largestIndex;
	}
	
	private void exchange(int a, int b) {
		Float		tempF;
		Integer		tempI;
		String		tempS;

		tempS = (String)this.items.elementAt(a);
		tempF = (Float)this.prices.elementAt(a);
		tempI = (Integer)this.quantities.elementAt(a);
	
		this.items.setElementAt((String)this.items.elementAt(b),a);
		this.items.setElementAt(tempS,b);

		this.prices.setElementAt((Float)this.prices.elementAt(b),a);
		this.prices.setElementAt(tempF,b);

		this.quantities.setElementAt((Integer)this.quantities.elementAt(b),a);
		this.quantities.setElementAt(tempI,b);

	}
	
	public void print() {
	    Date today=new Date();
		String item=" ";
		Float price;
		final float discount=100.0f;
		Integer quantity;
	    float itemtotal;
	    float subTotal=0f;
	    float tax;
	    float theDiscount=0f;
	    int i,j,maxSize;
/*printing the header of the receipt*/
	    System.out.println("======================");
  	    System.out.println("     MEGA  STORE");
  	    System.out.print(today.getDate()+"/");
  	    System.out.print((today.getMonth()+1)+"/");
  	    System.out.print((today.getYear()+1900)+" ");
  	    System.out.print(today.getHours()+":");
  	    System.out.println(today.getMinutes());
	    System.out.println("======================");
	    
/*counting the size of the longest item*/	    
    	item=(String)this.items.elementAt(0);
        maxSize=item.length();
	    for (i=1;i<this.items.size();i++){
	    	item=(String)this.items.elementAt(i);
	        if (maxSize<item.length()) {
	            maxSize=item.length();
	        }
        }
/*printing the lines with items*/
	    for (i=0;i<this.items.size();i++){
	    	item=(String)this.items.elementAt(i);
	    	price=(Float)this.prices.elementAt(i);
	    	quantity=(Integer)this.quantities.elementAt(i);
	    	System.out.print(item);
	    	/*adding spaces to match the longest item*/
            for (j=item.length();j<maxSize;j++){
                System.out.print(" ");
            }
	    	System.out.print("  "+price+"  "+quantity+"  ");
	    	itemtotal=price.floatValue()*quantity.intValue();
	    	subTotal=subTotal+itemtotal;
	    	System.out.println(itemtotal);
	    }
/*printing the footer of the receipt*/	    
	    System.out.println("======================");
	    tax=subTotal*0.07f;
	    System.out.println("SubTotal= $"+subTotal);
	    System.out.println("GST     = $"+tax);
	    if (subTotal>=discount) {
	    	theDiscount=subTotal*0.05f;
	        System.out.println("Discount= $"+theDiscount);
	    }
   	    System.out.println("Total   = $"+(subTotal+tax-theDiscount));

	    System.out.println("======================");
	 
	}
}