# Using a LINQ query in LINQPad

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(For more resources related to this topic, see here.)

# The standard version

We are going to implement a simple scenario: given a deck of 52 cards, we want to pick a random number of cards, and then take out all of the hearts. From this stack of hearts, we will discard the first two and take the next five cards (if possible), and order them by their face value for display.

You can try it in a C# program query in LINQPad:

`public static Random random = new Random();void Main(){  var deck = CreateDeck();  var randomCount = random.Next(52);  var hearts = new Card[randomCount];  var j = 0;  // take all hearts out  for(var i=0;i<randomCount;i++)  {    if(deck[i].Suit == "Hearts")    {      hearts[j++] = deck[i];    }  }  // resize the array to avoid null references  Array.Resize(ref hearts, j);     // check that we have at least 2 cards. If not, stop  if(hearts.Length <= 2)    return;  var count = 0;  // check how many cards we can take  count = hearts.Length - 2;  // the most we need to take is 5  if(count > 5) { count = 5; }  // take the cards  var finalDeck = new Card[count];  Array.Copy(hearts, 2, finalDeck, 0, count);  // now order the cards  Array.Sort(finalDeck, new CardComparer());  // Display the result  finalDeck.Dump();}public class Card{  public string Suit { get; set; }  public int Value { get; set; }}// Create the cards' deckpublic Card[] CreateDeck(){  var suits = new [] { "Spades", "Clubs",                         "Hearts", "Diamonds" };  var deck = new Card[52];  for(var i = 0; i < 52; i++)  {    deck[i] = new Card { Suit = suits[i / 13],                               FaceValue = i-(13*(i/13))+1 };  }  // randomly shuffle the deck  for (var i = deck.Length - 1; i > 0; i--)  {  var j = random.Next(i + 1);  var tmp = deck[j];  deck[j] = deck[i];   deck[i] = tmp;  }  return deck;}// CardComparer compare 2 cards against their face valuepublic class CardComparer : Comparer<Card>{  public override int Compare(Card x, Card y)  {    return x.FaceValue.CompareTo(y.FaceValue);  }}`

Even if we didn’t consider the CreateDeck() method, we had to do quite a few operations to produce the expected result (your values might be different as we are using random cards). The output is as follows:

Depending on the data, LINQPad will add contextual information. For example, in this sample it will add the bottom row with the sum of all the values (here, only FaceValue).

Also, if you click on the horizontal graph button, you will get a visual representation of your data, as shown in the following screenshot: