using System;
public class Program
{
public static void Main()
NrInt v0= new NrInt(3);
NrInt v1= new NrInt(4);
NrInt v2= new NrInt(5);
NrInt s0= v0+v1+v2;
}
public class NrInt{
public NrInt(int nr) { Nr =nr;}
public int Nr { get; set;}
public static NrInt operator +(NrInt a, NrInt b){
int c = a.Nr + b.Nr;
System.Console.WriteLine("x+y={0}+{1}={2}", a.Nr, b.Nr, c);
return new NrInt(c);