constructor overloading in c#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Constructer_Overloading
{
class CalculateNumber
{
private int num1, num2, total;
public CalculateNumber()
{
num1 = num2 = total = 0;
}
public CalculateNumber(int numb1,int numb2)
{
num1 = numb1;
num2 = numb2;
total = 0;
}
public void AddNumber()
{
total = num1 + num2;
}
public void Display()
{
Console.WriteLine("The Sum of two number is {0}",total);
}
static void Main(string[] args)
{
CalculateNumber cn1 = new CalculateNumber(50,50);
CalculateNumber cn2 = new CalculateNumber(4,-3);
cn1.AddNumber();
cn1.Display();
cn2.AddNumber();
cn2.Display();
Console.ReadLine();
}
}
}