Write a program in C# Sharp to convert a decimal number into binary without using an array

using System;  
public class Exercise41
{  
    public static void Main()
     {
     int n, i, j, binno=0,dn;
	Console.Write("\n\n");
    Console.Write("Convert a decimal number to binary without using array:\n");
    Console.Write("---------------------------------------------------------");
    Console.Write("\n\n");	 
     Console.Write("Enter a number to convert : ");
     n = Convert.ToInt32(Console.ReadLine());	 
     dn=n;
     i=1;
      for(j=n;j>0;j=j/2)
       {
        binno=binno+(n%2)*i;
        i=i*10;
        n=n/2;
       }
     
     Console.Write("\nThe Binary of {0} is {1}.\n\n",dn,binno);
  }
}