20 lines
466 B
Text
20 lines
466 B
Text
fun facti(n: Int) = when {
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n < 0 -> throw IllegalArgumentException("negative numbers not allowed")
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else -> {
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var ans = 1L
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for (i in 2..n) ans *= i
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ans
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}
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}
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fun factr(n: Int): Long = when {
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n < 0 -> throw IllegalArgumentException("negative numbers not allowed")
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n < 2 -> 1L
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else -> n * factr(n - 1)
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}
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fun main(args: Array<String>) {
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val n = 20
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println("$n! = " + facti(n))
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println("$n! = " + factr(n))
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}
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