Flatten a list: Difference between revisions
Content added Content deleted
(→Python: Added a variant illustrating non-recursive use of concatMap, avoiding mutation and error-based flow) |
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flattenList(nestList, flatList) |
flattenList(nestList, flatList) |
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println("Flattened : " + flatList) |
println("Flattened : " + flatList) |
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}</lang> |
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Or, using a more functional approach: |
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<lang scala> |
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fun flatten(list: List<*>): List<*> { |
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fun flattenElement(elem: Any?): Iterable<*> { |
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return if (elem is List<*>) |
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if (elem.isEmpty()) elem |
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else flattenElement(elem.first()) + flattenElement(elem.drop(1)) |
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else listOf(elem) |
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} |
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return list.flatMap { elem -> flattenElement(elem) } |
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}</lang> |
}</lang> |
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