Rational numbers contain an integer numerator and denominator.
Write the code to implement a class named **Rational** which stores
two private ints (numer and denom) with the following methods:
public Rational(int,int); //constructor that sets the numer and denom
public Rational(Rational); //copy constructor for a Rational object
public void setNumer(int); //sets the numerator to the paramter value
public int getNumer(); //returns the stored numerator
public void setDenom(int); //sets the denominator to the paramter value
public int getDenom(); //returns the stored denominator
//return a new Rational object that contains the reciprocal of the object that invokes the method.
public Rational reciprocal();
//returns a new Rational object that contains the product of the two paramteres.
public static Rational multiply(Rational a, Rational b);