using System;
namespace ConsoleApplication1
{
class Test
{
public int _n;
public static Test operator - (Test x, Test y)
{
Test t = new Test();
t._n = x._n - y._n;
return t;
}
}
class Program
{
static void Main(string[] args)
{
Test a = new Test();
a._n = 10;
Test b = new Test();
b._n = 3;
Test t = a - b;
Console.WriteLine(t._n);
}
}
}
/*
run:
7
*/