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C# Brainteasers on Using Block

What will be the output of following code

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

namespace JUSTFORFUN
{
    class Program
    {
        static void Main(string[] args)
        {
            using (Student s = new Student())
            {
                Console.WriteLine("Insed Using Bock");
            }
            Console.Read();
        }
    }

    class Student
    {
        
    }
}

Output : Build Error 1 'JUSTFORFUN.Student': type used in a using statement must be implicitly convertible to 'System.IDisposable

What it means is, if we need to use any type in using block that type should implement IDisposable interface. 


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