Let N = 12, and Secret encapsulate the function: f(x)

Then Secret is an additive function for all primes less than 12 (i.e. 2,3,5,7,11) iff:

Secret(2+3) = Secret(2) + Secret(3)

Secret(3+5) = Secret(3) + Secret(5)

Secret(5+7) = Secret(5) + Secret(7)

Secret(7+11) = Secret(7) + Secret(11)

Secret returnMe = (int x) -> x;

Secret add5Divide2 = (int x) -> {

x += 5;

x /= 2;

return x;

};

System.out.print("Is returnMe additive? ");

System.out.println(FunctionCheck.isAdditiveFunction(returnMe, 100)); //true

System.out.print("Is add5Divide2 additive? ");

System.out.println(FunctionCheck.isAdditiveFunction(add5Divide2, 4)); //false