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

public class MainClass {
    public static void Main() {
        IEnumerable<int> intSequence = Enumerable.Range(1, 10);
        foreach (int i in intSequence)
            Console.WriteLine(i);
        double average = intSequence.Average();
        Console.WriteLine("Here is the average:  {0}", average);
    }
}

    

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

public class MainClass {
    public static void Main() {
        int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };

        double averageNum = numbers.Average();

        Console.WriteLine("The average number is {0}.", averageNum);
    }
}

    

   
 

using System;
using System.Collections.Generic;
using System.Linq;
public class MainClass {
    public static void Main() {
        int[] numbers = { 10, 9, 8, 7, 6 };
        bool hasTheNumberNine = numbers.Contains(9);          // true
        bool hasMoreThanZeroElements = numbers.Any();          // true
        bool hasAnOddElement = numbers.Any(n => n % 2 == 1);  // true
    }
}

    

   
 

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

public class MainClass {
    public static void Main() {
        string[] presidents = {"G", "H", "a", "H", "over", "Jack"};
        bool any = presidents.Any(s => s.StartsWith("A"));
        Console.WriteLine(any);
    }
}

    

   
 

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

public class MainClass {
    public static void Main() {
        string[] presidents = {"G", "H", "a", "H", "over", "Jack"};
        bool any = presidents.Any(s => s.StartsWith("Z"));
        Console.WriteLine(any);
    }
}

    

   
 

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

public class MainClass{
   public static void Main(){
       int[] numbers = { 2, 6, 1, 56, 102 };
       Console.Write(numbers.All(e => e % 2 == 0) ? "Yes, they are" : "No, they aren't");
   }
}

    

   
 

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

public class MainClass {
    public static void Main() {
        int[] numbers = { 1, 11, 3, 19, 41, 65, 19 };

        bool onlyOdd = numbers.All(n => n % 2 == 1);

        Console.WriteLine("The list contains only odd numbers: {0}", onlyOdd);
    }
}