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Converting while to foreach

Previously, you wrote a while loop in the imperative style to find and print the number of points to bust for five hands (one for each player) in a round of Twenty-One:

// Define counter variable
var i = 0

// Create list with five hands of Twenty-One
var hands = List(16, 21, 8, 25, 4)

// Loop through hands
while(i < hands.length) {
  // Find and print number of points to bust
  println(pointsToBust(hands(i)))
  // Increment the counter variable
  i += 1
}

In this exercise, you'll convert that code to a more functional, Scala-preferred style using the foreach method. The bust function is already defined for you. A modified pointsToBust function (with println) is provided in the sample code.

Este exercício faz parte do curso

Introduction to Scala

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Instruções do exercício

  • Call the foreach method on the hands array of arrays, looping through each round to find the number of points to bust using the pointsToBust function.

Exercício interativo prático

Experimente este exercício completando este código de exemplo.

// Find the number of points that will cause a bust
def pointsToBust(hand: Int) = {
  // If the hand is a bust, 0 points remain
  if (bust(hand))
    println(0)
  // Otherwise, calculate the difference between 21 and the current hand
  else
    println(21 - hand)
}

// Create list with five hands of Twenty-One
var hands = List(16, 21, 8, 25, 4)

// Loop through hands, finding each hand's number of points to bust
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