为什么在第一个图片代码不执行，但在第二个呢？

Question

Exactly i know how to solve this problem, but i don't understand why this solution works.

I mean what the first( 1 ) piece of code dosn't output anything, but the second(2) works correctly.

I need an explanation - why.

(1).

    class Greetings
    {
        static void Main(string[] args)
        {
            cube(5);
            Console.ReadKey();
        }
        static int cube(int num)
        {
            int result = num * num;
            return result;
        }
    }

(2).

    class Greetings
    {
        static void Main(string[] args)
        {
            Console.WriteLine(cube(5));
            Console.ReadKey();
        }
        static int cube(int num)
        {
            int result = num * num * num;
            return result;
        }
    }

It has to output 125, but it doesn't output anything.

Answer 1

Because you don't print the answer with the Console.WriteLine(); method in the first piece of code. The result is returned but not printed to the console, because there is no Console.WriteLine(); .