@FunctionalInterface
interface Add
{
    int addition(int a, int b);
}

/**
 * 
 * In Java lambda expression, if there is only one statement, you may
 * or may not use return keyword.
 * 
 * Java Lambda Expression Example: Without return keyword
 *
 */
public class LambdaDemo
{

    public static void main(String[] args)
    {
        // Lambda expression without return keyword.
        Add add = (a, b) -> (a + b);

        int sum = add.addition(10, 20);
        System.out.println("sum = " + sum);
    }

}

sum = 30