How do you convert this method into a lambda expression?
public int square(int x) { return x * x; }
Function<Integer, Integer> squareLambda = x -> return x * x;
Function<Integer, Integer> squareLambda = x -> x * x;
Function<Integer, Integer> squareLambda = () -> { return x * x };
Function<Integer, Integer> squareLambda = (int x) -> { x * x };