using System;

public class Program

{

    public static void Main(string[]args)

    {

        string x,y,z;

        x="1";

        y="2";

        z=x+y; 

        Console.WriteLine(z);

        //////////////////////////////////////////////////////////////////////////////

        int a=1,b=2,c;

        c=a+b;

        Console.WriteLine("the sum of "+a+" and "+b+" is "+ c);

    }

}