lm-tecniche-di-programmazione/src/main/kotlin/it/norangeb/algorithms/sorting/Countingsort.kt

51 lines
1.6 KiB
Kotlin

/*
* MIT License
*
* Copyright (c) 2019 norangebit
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/
package it.norangeb.algorithms.sorting
object Countingsort {
fun sort(array: Array<Int>, from: Int, to: Int) {
if (from >= to)
return
val range = to - from + 1
val bucket = Array(range) { 0 }
array.forEach { bucket[it - from] += 1 }
bucket.forEachIndexed { index, i ->
if (index != 0) {
bucket[index] += bucket[index - 1]
}
}
val aux = array.clone()
aux.forEach {
array[--bucket[it - from]] = it
}
}
}