31 lines
715 B
Text
31 lines
715 B
Text
object Knuth {
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internal val gen = java.util.Random()
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}
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fun <T> Array<T>.shuffle(): Array<T> {
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val a = clone()
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var n = a.size
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while (n > 1) {
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val k = Knuth.gen.nextInt(n--)
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val t = a[n]
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a[n] = a[k]
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a[k] = t
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}
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return a
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}
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fun main(args: Array<String>) {
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val str = "abcdefghijklmnopqrstuvwxyz".toCharArray()
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(1..10).forEach {
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val s = str.toTypedArray().shuffle().toCharArray()
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println(s)
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require(s.toSortedSet() == str.toSortedSet())
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}
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val ia = arrayOf(1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
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(1..10).forEach {
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val s = ia.shuffle()
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println(s.distinct())
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require(s.toSortedSet() == ia.toSet())
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}
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}
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