public class main {
@FunctionalInterface
interface Function3 <A, B, C, R> {
//R is like Return, but doesn't have to be last in the list nor named R.
public R apply (A a, B b, C c);
}
public static void main (String [] args) {
Function3 <String, Integer, Double, Double> multiAdder = (a, b, c) -> {
return Double.parseDouble (a) + b + c;
};
System.out.println (multiAdder.apply ("22.4", 2, 40.0));
}
}