csharp

using System;

class Program
{
    static void Main()
    {
        Console.WriteLine("Hello, World!");
    }
}

using System;

class Program
{
    static void Main()
    {
        string name = "Santosh";
        int age = 25;
        double price = 19.99;
        bool isLearning = true;

        Console.WriteLine($"Name: {name}");
        Console.WriteLine($"Age: {age}");
        Console.WriteLine($"Price: {price}");
        Console.WriteLine($"Is Learning: {isLearning}");
    }
}

using System;

class Program
{
    static void Main()
    {
        int a = 10, b = 5;

        Console.WriteLine("Addition: " + (a + b));
        Console.WriteLine("Subtraction: " + (a - b));
        Console.WriteLine("Multiplication: " + (a * b));
        Console.WriteLine("Division: " + (a / b));
        Console.WriteLine("Modulus: " + (a % b));
    }
}

using System;

class Program
{
    static void Main()
    {
        int age = 18;

        if (age >= 18)
        {
            Console.WriteLine("Eligible for voting");
        }
        else
        {
            Console.WriteLine("Not eligible for voting");
        }
    }
}

using System;

class Program
{
    static void Main()
    {
        int day = 3;
        string dayName;

        switch (day)
        {
            case 1:
                dayName = "Monday";
                break;
            case 2:
                dayName = "Tuesday";
                break;
            case 3:
                dayName = "Wednesday";
                break;
            case 4:
                dayName = "Thursday";
                break;
            case 5:
                dayName = "Friday";
                break;
            default:
                dayName = "Weekend";
                break;
        }

        Console.WriteLine("Day: " + dayName);
    }
}

using System;

class Program
{
    static void Main()
    {
        // For Loop
        for (int i = 1; i <= 5; i++)
        {
            Console.WriteLine($"Santosh learning C# - Iteration: {i}");
        }

        // While Loop
        int count = 1;
        while (count <= 3)
        {
            Console.WriteLine($"Dhruv exploring C# - Attempt: {count}");
            count++;
        }
    }
}

using System;

class Program
{
    static void Main()
    {
        string[] names = { "Santosh", "Kumar", "Dhruv", "Pynfinity" };

        for (int i = 0; i < names.Length; i++)
        {
            Console.WriteLine($"Name {i + 1}: {names[i]}");
        }
    }
}

using System;

class Program
{
    static void Greet(string name)
    {
        Console.WriteLine($"Hello, {name}! Welcome to C#.");
    }

    static void Main()
    {
        Greet("Santosh");
        Greet("Kumar");
    }
}

using System;

class Person
{
    public string Name { get; set; }
    public int Age { get; set; }

    // Constructor
    public Person(string name, int age)
    {
        Name = name;
        Age = age;
    }

    public void Introduce()
    {
        Console.WriteLine($"Hi, my name is {Name} and I am {Age} years old.");
    }
}

class Program
{
    static void Main()
    {
        Person person1 = new Person("Santosh", 25);
        Person person2 = new Person("Kumar", 30);

        person1.Introduce();
        person2.Introduce();
    }
}

using System;

class Program
{
    static void Main()
    {
        try
        {
            int[] numbers = { 1, 2, 3 };
            Console.WriteLine(numbers[5]); // Index out of range
        }
        catch (IndexOutOfRangeException ex)
        {
            Console.WriteLine("Error: " + ex.Message);
        }
        finally
        {
            Console.WriteLine("This block always runs.");
        }
    }
}

using System;

class Animal
{
    public string Name { get; set; }

    public void Speak()
    {
        Console.WriteLine($"{Name} makes a sound.");
    }
}

class Dog : Animal
{
    public void Bark()
    {
        Console.WriteLine($"{Name} barks.");
    }
}

class Program
{
    static void Main()
    {
        Dog dog = new Dog();
        dog.Name = "Buddy";
        dog.Speak();
        dog.Bark();
    }
}

using System;

class Animal
{
    public virtual void Speak()
    {
        Console.WriteLine("The animal makes a sound.");
    }
}

class Dog : Animal
{
    public override void Speak()
    {
        Console.WriteLine("The dog barks.");
    }
}

class Program
{
    static void Main()
    {
        Animal myAnimal = new Animal();
        myAnimal.Speak();

        Dog myDog = new Dog();
        myDog.Speak();
    }
}

using System;

interface IDriveable
{
    void Drive();
}

class Car : IDriveable
{
    public void Drive()
    {
        Console.WriteLine("The car is driving.");
    }
}

class Program
{
    static void Main()
    {
        IDriveable myCar = new Car();
        myCar.Drive();
    }
}

using System;
using System.Linq;

class Program
{
    static void Main()
    {
        int[] numbers = { 5, 10, 15, 20, 25 };

        var result = from number in numbers
                     where number > 10
                     select number;

        foreach (var number in result)
        {
            Console.WriteLine(number);
        }
    }
}

using System;
using System.IO;

class Program
{
    static void Main()
    {
        string filePath = "example.txt";

        // Writing to a file
        File.WriteAllText(filePath, "This is a test file written by Santosh.");

        // Reading from the file
        string fileContent = File.ReadAllText(filePath);
        Console.WriteLine(fileContent);
    }
}

using System;

delegate void GreetDelegate(string name);

class Program
{
    static void Greet(string name)
    {
        Console.WriteLine($"Hello, {name}!");
    }

    static void Main()
    {
        GreetDelegate greet = new GreetDelegate(Greet);
        greet("Santosh");
    }
}

using System;

class Program
{
    static void Main()
    {
        Func<int, int, int> add = (x, y) => x + y;
        Console.WriteLine($"Sum: {add(5, 10)}");

        Func<string, bool> isShortName = name => name.Length <= 5;
        Console.WriteLine($"Is 'Dhruv' short name? {isShortName("Dhruv")}");
    }
}

using System;
using System.Threading.Tasks;

class Program
{
    static async Task Main()
    {
        await DoTaskAsync();
        Console.WriteLine("Main method complete");
    }

    static async Task DoTaskAsync()
    {
        await Task.Delay(2000);
        Console.WriteLine("Task complete after delay");
    }
}