20 lines
499 B
Scala
20 lines
499 B
Scala
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import scala.util.Random.shuffle
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import scala.annotation.tailrec
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// ...
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def isBalanced(str: String): Boolean = isBalanced(str.toList, balance = 0)
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@tailrec
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def isBalanced(str: List[Char], balance: Int = 0): Boolean =
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str match {
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case _ if (balance < 0) => false
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case Nil => balance == 0
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case char :: rest =>
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val newBalance = char match {
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case '[' => balance + 1
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case ']' => balance -1
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}
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isBalanced(rest, newBalance)
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}
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