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

class LinqDemo {
    static void Main() {
        string[] names = { "J", "P", "G", "P" };

        IEnumerable<string> query = names
          .Where(n => n.Contains("a"))
          .OrderBy(n => n.Length)
          .Select(n => n.ToUpper());

        foreach (string name in query) Console.Write(name + "|");
    }
}

    

   
 


using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
    public static void Main() {
        string[] presidents = {"A", "Ar", "Buc", "Bush", "Carte", "Clevel"};

        var nameObjs = presidents.Select(p => new { p, p.Length });

        foreach (var item in nameObjs)
            Console.WriteLine(item);
    }
}

    

   
 

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
    public static void Main() {
        string[] presidents = {"A", "Ar", "Buc", "Bush", "Carte", "Clevel"};
        var nameObjs = presidents.Select(p => new { LastName = p, Length = p.Length });
        foreach (var item in nameObjs)
            Console.WriteLine("{0} is {1} characters long.", item.LastName, item.Length);

    }
}

    

   
 

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
    public static void Main() {
        string[] presidents = {"A", "B", "Bu", "Bush", "C", "Cl"};

        var nameObjs = presidents.Select((p, i) => new { Index = i, LastName = p });

        foreach (var item in nameObjs)
            Console.WriteLine("{0}. {1}", item.Index + 1, item.LastName);

    }
}

    

   
 

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
    public static void Main() {
        string[] presidents = {"Ad", "Ar", "Bu", "Bu", "Ca", "Cl"};

        IEnumerable<string> sequence = presidents.Where((p, i) => (i &amp; 1) == 1);

        foreach (string s in sequence)
            Console.WriteLine("{0}", s);

    }
}

    

   
 
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};
        var numsPlusOne =
            from n in numbers
            select n + 1;

        Console.WriteLine("Numbers + 1:");
        foreach (var i in numsPlusOne) {
            Console.WriteLine(i);
        }
    }
}

    

   
 
using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
public class MainClass {
    public static void Main() {
        string[] presidents = {"ant", "arding", "arrison", "eyes", "over", "ackson"};
        IEnumerable<string> items = presidents.OrderBy(s => s.Length);
        foreach (string item in items)
            Console.WriteLine(item);
    }
}