public interface AFinancialHistory {
    // Transaction recording
    public void receive(int amount, String source);
    public void spend(int amount, String reason);

    // Inquiries
    public int cashOnHand();
    public int totalReceivedFrom(String source);
    public int totalSpentFor(String reason);
}

public class FinancialHistory implements AFinancialHistory {
    private int cashOnHand;
    private java.util.Hashtable incomes, expenditures;

    // Transaction recording
    public void receive(int amount, String source) {
	incomes.put(source,
		    new Integer(this.totalReceivedFrom(source) + amount));
	this.cashOnHand = this.cashOnHand + amount;
    }

    public void spend(int amount, String reason) {
	expenditures.put(reason,
			 new Integer(this.totalSpentFor(reason) + amount));
	this.cashOnHand = this.cashOnHand - amount;
    }

    // Inquiries
    public int cashOnHand() {
	return this.cashOnHand;
    }

    public int totalReceivedFrom(String source) {
	return incomes.containsKey(source) ?
	         ((Integer) incomes.get(source)).intValue() : 0;
    }

    public int totalSpentFor(String reason) {
	return expenditures.containsKey(reason) ?
	         ((Integer) expenditures.get(reason)).intValue() : 0;
    }

    // Instance creation
    public FinancialHistory(int amount) {
	this.cashOnHand = amount;
	this.incomes = new java.util.Hashtable();
	this.expenditures = new java.util.Hashtable();
    }
}

public interface ADeductibleHistory extends AFinancialHistory {
    // Transaction recording
    public void spendDeductible(int amount, String reason);
    public void spend(int amount, String reason, int deductibleAmount);

    // Inquiries
    public int totalDeductions();
}

public class DeductibleHistory extends FinancialHistory 
    implements ADeductibleHistory
{
    private int deductibleExpenditures;

    // Transaction recording
    public void spendDeductible(int amount, String reason) {
	this.spend(amount, reason);
	this.deductibleExpenditures = this.deductibleExpenditures + amount;
    }

    public void spend(int amount, String reason, int deductibleAmount) {
	this.spend(amount, reason);
	this.deductibleExpenditures = this.deductibleExpenditures + deductibleAmount;
    }

    // Inquiries
    public int totalDeductions() {
	return this.deductibleExpenditures;
    }

    // Instance creation
    public DeductibleHistory(int amount) {
	super(amount);
	this.deductibleExpenditures = 0;
    }
}

public class RunFinancialHistory {
    public static void main(String [] args) {
	DeductibleHistory h = new DeductibleHistory(100);
	System.out.println(h.cashOnHand());
    }
}