public class Lambda1 { 
     
    interface Function<T> { 
        T compute(T n); 
    } 

    static <T> T operate(Function<T> f, T data) { 
        return f.compute(data); 
    } 

    public static void main(String[] args) { 
        System.out.println(operate((i) -> i * 2, 3)); 
    } 

}