using System;

public class Program

{

    public int F(int x)

    {

        Console.WriteLine(x);

        return x;

    }

    public void Main()

    {

        // equivalent to

        /*

        var unnamed1 = F(1);

        var unnamed2 = F(2);

        var unnamed3 = F(3);

        var z = unnamed1 + (unnamed2 + unnamed3);

        */

        var z = F(1) + (F(2) + F(3));

        Console.WriteLine(z);

    }

}