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if expressions result in a value

In Scala, if is an expression, and expressions result in a value. That means the result of if can be assigned to a variable.

Imagine you're playing Twenty-One. You receive cards from the dealer and would like to know where your hand stands. If your hand is greater than 21, a "Bust!" message informing us of this result would be disappointing but helpful. If our hand is 21 exactly, the congratulatory "Twenty-One!" message applies. If less than 21, the program should ask us, "Hit or stay?"

In this exercise, you'll improve the code you wrote last exercise. You'll write an if-else if-else expression to store an appropriate message for the player's current hand in a variable. The card variables you need are already defined.

Diese Übung ist Teil des Kurses

Introduction to Scala

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Anleitung zur Übung

  • Read the provided code, then fill in the type annotation for the informPlayer variable.
  • Write appropriate if, else if, and else conditions based on the provided code.
  • Change fiveSpades to fourSpades, then click "Run Code" and observe the output.
  • Change fourSpades to threeSpades, then click "Submit Answer".

Interaktive Übung

Versuche dich an dieser Übung, indem du diesen Beispielcode vervollständigst.

// Point value of a player's hand
val hand = sevenClubs + kingDiamonds + fiveSpades

// Inform a player where their current hand stands
val informPlayer: ___ = {
  ___
    "Bust! :("
  ___
    "Twenty-One! :)"
  ___
    "Hit or stay?"
}

// Print the message
print(informPlayer)
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