public class MainProgram {

    public static void main(String[] args) {
        Money a = new Money(10, 0);
        Money b = new Money(3, 50);

        Money c = a.minus(b);

        System.out.println(a);  // 10.00e
        System.out.println(b);  // 3.50e
        System.out.println(c);  // 6.50e

        c = c.minus(a);       // NB: a new Money object is created, and is placed "at the end of the strand connected to c"
//  the old 6.5 euros at the end of the strand disappears and the Java garbage collector takes care of it

        System.out.println(a);  // 10.00e
        System.out.println(b);  // 3.50e
        System.out.println(c);  // 0.00e

}
}



public class Money {

    private final int euros;
    private final int cents;

    public Money(int euros, int cents) {

        if (cents > 99) {
            euros = euros + cents / 100;
            cents = cents % 100;
        }

        this.euros = euros;
        this.cents = cents;
    }

    public int euros() {
        return this.euros;
    }

    public int cents() {
        return this.cents;
    }

    public String toString() {
        String zero = "";
        if (this.cents < 10) {
            zero = "0";
        }

        return this.euros + "." + zero + this.cents + "e";
    }

    public boolean lessThan(Money compared) {
        if (this.euros < compared.euros) {
            return true;
        }
        if (this.euros == compared.euros && this.cents < compared.cents) {
            return true;
        }
        return false;
    }

    public Money plus(Money addition) {
        Money newMoney = new Money(addition.euros + this.euros, addition.cents + this.cents);// create a new Money object that has the correct worth

        return newMoney;
    }

    public Money minus(Money decreaser) {

       int e =decreaser.euros-this.euros;
       int c= decreaser.cents-this.cents;


        Money newMinus = new Money (e,c);

        return newMinus;

    }

}