Sort using a custom comparator: Difference between revisions
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m (added category.) |
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printArray("Sorted:", strings) |
printArray("Sorted:", strings) |
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}</lang> |
}</lang> |
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{{out}} |
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<pre>Unsorted: [Here, are, some, sample, strings, to, be, sorted] |
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Sorted: [strings, sample, sorted, Here, some, are, be, to]</pre> |
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A more idiomatic version (1.3): |
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<lang kotlin>fun main(args: Array<String>) { |
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val strings = listOf("Here", "are", "some", "sample", "strings", "to", "be", "sorted") |
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println("Unsorted: $strings") |
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// sort by content first then by length => no need for a custom comparator since sortedByDescending is stable |
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val sorted = strings.sorted().sortedByDescending { it.length } |
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println("Sorted: $sorted") |
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}</lang> |
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Using a custom comparator as requested by task description: |
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<lang kotlin>fun main(args: Array<String>) { |
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val strings = listOf("Here", "are", "some", "sample", "strings", "to", "be", "sorted") |
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println("Unsorted: $strings") |
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val sorted = strings.sortedWith ( |
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kotlin.Comparator { a, b -> |
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compareValues(b.length, a.length).let { |
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if (it == 0) compareValues(a, b) |
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else it |
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} |
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}) |
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println("Sorted: $sorted") |
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}</lang> |
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Faster when computing length only once per value ([[wp:Schwartzian transform|Schwartzian transform]]): |
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<lang kotlin>fun main(args: Array<String>) { |
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val strings = listOf("Here", "are", "some", "sample", "strings", "to", "be", "sorted") |
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println("Unsorted: $strings") |
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val sorted = strings.map { Pair(it, it.length) }.sortedWith ( |
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kotlin.Comparator { a, b -> |
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compareValues(b.second, a.second).let { |
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if (it == 0) compareValues(a.first, b.first) |
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else it |
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} |
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}).map { it.first } |
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println("Sorted: $sorted") |
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}</lang> |
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{{out}} |
{{out}} |
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