using System;

public class Program

{

    public static void Main()

    {

        int a1=30;

        ++a1;

        Console.WriteLine(a1);

​

        int a2=++a1;

        Console.WriteLine(a2);

        int age1=30;  

        age1++;

        Console.WriteLine(age1);

        int mark1=30;  

        int mark2=mark1++;

        Console.WriteLine(mark2);

    }

}