using System;

using System.Text;

public class Program

{

    public static void Main()

    {

        // StringBuilder capacity is automatically doubled at a certain point to accommodate more characters. 

        // This increase in capacity might differ when initialized as a constructor argument.

        StringBuilder sb = new StringBuilder("123456", 5);

        Console.WriteLine(sb.Length); // 6

        Console.WriteLine(sb.Capacity); // capacity equal to length : 6

        sb.Append("78901234567");

        Console.WriteLine(sb.Length); // 17

        Console.WriteLine(sb.Capacity); // capacity equal to length : 17

        Console.WriteLine(sb.ToString());

        Console.WriteLine("\n-------------------Separator---------------------\n");

        StringBuilder sb1 = new StringBuilder(5);

        Console.WriteLine(sb1.Capacity); // initial capacity : 5

        sb1.Append("123456");

        Console.WriteLine(sb1.Length); // 6

        Console.WriteLine(sb1.Capacity); // capacity doubled : 10

        Console.WriteLine(sb1.ToString());

​

​

    }

}