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rhaendelrhaendel
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Move the MutableRingList to collections package
It already is implemented in a generic way.
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-127
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4 files changed

+136
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‎src/main/kotlin/de/ronny_h/aoc/extensions/collections/MutableRingList.kt‎

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package de.ronny_h.aoc.extensions.collections
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class MutableRingList<T>(initialList: List<T>) {
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private val list: MutableList<T> = initialList.toMutableList()
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private var offset = 0
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companion object {
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fun <T> mutableRingListOf(vararg elements: T): MutableRingList<T> = MutableRingList(elements.toList())
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fun mutableRingListOf(elements: String): MutableRingList<Char> = MutableRingList(elements.toList())
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}
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operator fun get(index: Int) = list[(index + offset) % list.size]
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operator fun set(index: Int, value: T) {
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list[(index + offset) % list.size] = value
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}
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/**
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* Makes [n] elements move from the end to the front, but maintain their order otherwise.
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*/
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fun shiftRight(n: Int): MutableRingList<T> {
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check(n <= list.size) { "the number of items to spin must be smaller than or equal to the list's length" }
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offset = (offset + list.size - n) % list.size
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return this
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}
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/**
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* Swaps the elements at [indexA] and [indexB].
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*/
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fun swap(indexA: Int, indexB: Int): MutableRingList<T> {
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val tmp = get(indexA)
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set(indexA, get(indexB))
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set(indexB, tmp)
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return this
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}
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/**
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* Swaps the positions of the specified elements [elemA] and [elemB].
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* If not unique, only their first occurrences are swapped.
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*/
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fun swap(elemA: T, elemB: T): MutableRingList<T> {
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val indexA = list.indexOf(elemA)
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val indexB = list.indexOf(elemB)
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require(indexA >= 0) { "$elemA is not in the list" }
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require(indexB >= 0) { "$elemB is not in the list" }
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list[indexA] = elemB
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list[indexB] = elemA
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return this
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}
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/**
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* @return A snapshot of the current state of this [MutableRingList]
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*/
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fun toList(): List<T> = list.subList(offset, list.size) + list.subList(0, offset)
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override fun toString(): String = toList().toString()
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fun toJoinedString(): String = toList().joinToString("")
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}

‎src/main/kotlin/de/ronny_h/aoc/year2017/day16/PermutationPromenade.kt‎

Lines changed: 2 additions & 59 deletions
Original file line numberDiff line numberDiff line change
@@ -1,8 +1,9 @@
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package de.ronny_h.aoc.year2017.day16
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import de.ronny_h.aoc.AdventOfCode
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import de.ronny_h.aoc.extensions.collections.MutableRingList
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import de.ronny_h.aoc.extensions.collections.MutableRingList.Companion.mutableRingListOf
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import de.ronny_h.aoc.year2017.day16.DanceMove.*
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import de.ronny_h.aoc.year2017.day16.MutableRingList.Companion.mutableRingListOf
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fun main() = PermutationPromenade().run("kgdchlfniambejop", "fjpmholcibdgeakn")
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@@ -69,61 +70,3 @@ fun List<String>.parseDanceMoves() = single().split(",").map {
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else -> error("unknown move: $it")
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}
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}
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class MutableRingList<T>(initialList: List<T>) {
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private val list: MutableList<T> = initialList.toMutableList()
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private var offset = 0
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companion object {
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fun <T> mutableRingListOf(vararg elements: T): MutableRingList<T> = MutableRingList(elements.toList())
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fun mutableRingListOf(elements: String): MutableRingList<Char> = MutableRingList(elements.toList())
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}
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operator fun get(index: Int) = list[(index + offset) % list.size]
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operator fun set(index: Int, value: T) {
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list[(index + offset) % list.size] = value
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}
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/**
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* Makes [n] elements move from the end to the front, but maintain their order otherwise.
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*/
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fun shiftRight(n: Int): MutableRingList<T> {
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check(n <= list.size) { "the number of items to spin must be smaller than or equal to the list's length" }
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offset = (offset + list.size - n) % list.size
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return this
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}
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/**
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* Swaps the elements at [indexA] and [indexB].
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*/
100-
fun swap(indexA: Int, indexB: Int): MutableRingList<T> {
101-
val tmp = get(indexA)
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set(indexA, get(indexB))
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set(indexB, tmp)
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return this
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}
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/**
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* Swaps the positions of the specified elements [elemA] and [elemB].
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* If not unique, only their first occurrences are swapped.
110-
*/
111-
fun swap(elemA: T, elemB: T): MutableRingList<T> {
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val indexA = list.indexOf(elemA)
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val indexB = list.indexOf(elemB)
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require(indexA >= 0) { "$elemA is not in the list" }
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require(indexB >= 0) { "$elemB is not in the list" }
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list[indexA] = elemB
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list[indexB] = elemA
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return this
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}
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/**
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* @return A snapshot of the current state of this [MutableRingList]
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*/
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fun toList(): List<T> = list.subList(offset, list.size) + list.subList(0, offset)
125-
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override fun toString(): String = toList().toString()
127-
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fun toJoinedString(): String = toList().joinToString("")
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}

‎src/test/kotlin/de/ronny_h/aoc/extensions/collections/MutableRingListTest.kt‎

Lines changed: 75 additions & 0 deletions
Original file line numberDiff line numberDiff line change
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package de.ronny_h.aoc.extensions.collections
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import de.ronny_h.aoc.extensions.collections.MutableRingList.Companion.mutableRingListOf
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import io.kotest.core.spec.style.StringSpec
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import io.kotest.matchers.shouldBe
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class MutableRingListTest : StringSpec({
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"a MutableRingList<Char> can be created from a variable amounts of Chars and toString() generates a nice representation" {
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mutableRingListOf('a', 'b', 'c', 'd', 'e').toString() shouldBe "[a, b, c, d, e]"
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}
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"a MutableRingList<Char> can be created from a String and toJoinedString() recreates that String" {
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mutableRingListOf("abcde").toJoinedString() shouldBe "abcde"
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}
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"get(index) returns the element at index" {
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mutableRingListOf("abcde").get(2) shouldBe 'c'
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mutableRingListOf("abcde")[2] shouldBe 'c'
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}
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"set(index, value) sets the value at index" {
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val list = mutableRingListOf("abcde")
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list.set(2, 'z')
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list[2] shouldBe 'z'
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list[0] = 'y'
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list[0] shouldBe 'y'
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}
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"shiftRight() moves elements from the end to the front" {
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mutableRingListOf("abcde").shiftRight(1).toJoinedString() shouldBe "eabcd"
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mutableRingListOf("abcde").shiftRight(2).toJoinedString() shouldBe "deabc"
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mutableRingListOf("abcde").shiftRight(1).shiftRight(1).toJoinedString() shouldBe "deabc"
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mutableRingListOf("abcde").shiftRight(3).toJoinedString() shouldBe "cdeab"
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mutableRingListOf("abcde").shiftRight(1).shiftRight(2).toJoinedString() shouldBe "cdeab"
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mutableRingListOf("abcde").shiftRight(5).toJoinedString() shouldBe "abcde"
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}
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"get after shiftRight returns the shifted elements" {
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val list = mutableRingListOf("abcde").shiftRight(1)
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list[0] shouldBe 'e'
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list[4] shouldBe 'd'
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}
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"set after shiftRight sets the element at the shifted position" {
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val list = mutableRingListOf("abcde").shiftRight(1)
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list[0] = 'x'
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list[0] shouldBe 'x'
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list[4] shouldBe 'd'
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}
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"toList returns the modified state" {
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val list = mutableRingListOf("abcde")
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.shiftRight(2)
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.swap(0, 1)
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list.toList() shouldBe listOf('e', 'd', 'a', 'b', 'c')
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}
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"swap(indexA, indexB) exchanges the elements at the given indexes" {
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mutableRingListOf("abcde").swap(3, 4).toJoinedString() shouldBe "abced"
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mutableRingListOf("abcde").swap(0, 4).toJoinedString() shouldBe "ebcda"
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mutableRingListOf("abcde").swap(3, 3).toJoinedString() shouldBe "abcde"
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}
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"swap(elemA, elemB) exchanges the elements by their name" {
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mutableRingListOf("abcde").swap('d', 'e').toJoinedString() shouldBe "abced"
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mutableRingListOf("abcde").swap('a', 'e').toJoinedString() shouldBe "ebcda"
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mutableRingListOf("abcde").swap('c', 'c').toJoinedString() shouldBe "abcde"
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}
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})

‎src/test/kotlin/de/ronny_h/aoc/year2017/day16/PermutationPromenadeTest.kt‎

Lines changed: 0 additions & 68 deletions
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,6 @@
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package de.ronny_h.aoc.year2017.day16
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import de.ronny_h.aoc.year2017.day16.DanceMove.*
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import de.ronny_h.aoc.year2017.day16.MutableRingList.Companion.mutableRingListOf
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import io.kotest.core.spec.style.StringSpec
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import io.kotest.matchers.shouldBe
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@@ -13,73 +12,6 @@ class PermutationPromenadeTest : StringSpec({
1312
input.parseDanceMoves() shouldBe listOf(Spin(1), Exchange(3, 4), Partner('e', 'b'))
1413
}
1514

16-
"a MutableRingList<Char> can be created from a variable amounts of Chars and toString() generates a nice representation" {
17-
mutableRingListOf('a', 'b', 'c', 'd', 'e').toString() shouldBe "[a, b, c, d, e]"
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}
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20-
"a MutableRingList<Char> can be created from a String and toJoinedString() recreates that String" {
21-
mutableRingListOf("abcde").toJoinedString() shouldBe "abcde"
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}
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"MutableRingList: get" {
25-
mutableRingListOf("abcde").get(2) shouldBe 'c'
26-
mutableRingListOf("abcde")[2] shouldBe 'c'
27-
}
28-
29-
"MutableRingList: set" {
30-
val list = mutableRingListOf("abcde")
31-
32-
list.set(2, 'z')
33-
list[2] shouldBe 'z'
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35-
list[0] = 'y'
36-
list[0] shouldBe 'y'
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}
38-
39-
"MutableRingList: programs can be spun" {
40-
mutableRingListOf("abcde").shiftRight(1).toJoinedString() shouldBe "eabcd"
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mutableRingListOf("abcde").shiftRight(2).toJoinedString() shouldBe "deabc"
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mutableRingListOf("abcde").shiftRight(1).shiftRight(1).toJoinedString() shouldBe "deabc"
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mutableRingListOf("abcde").shiftRight(3).toJoinedString() shouldBe "cdeab"
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mutableRingListOf("abcde").shiftRight(1).shiftRight(2).toJoinedString() shouldBe "cdeab"
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48-
mutableRingListOf("abcde").shiftRight(5).toJoinedString() shouldBe "abcde"
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}
50-
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"MutableRingList: get after spin" {
52-
val list = mutableRingListOf("abcde").shiftRight(1)
53-
list[0] shouldBe 'e'
54-
list[4] shouldBe 'd'
55-
}
56-
57-
"MutableRingList: set after spin" {
58-
val list = mutableRingListOf("abcde").shiftRight(1)
59-
list[0] = 'x'
60-
list[0] shouldBe 'x'
61-
list[4] shouldBe 'd'
62-
}
63-
64-
"MutableRingList: toList returns the modified state" {
65-
val list = mutableRingListOf("abcde")
66-
.shiftRight(2)
67-
.swap(0, 1)
68-
list.toList() shouldBe listOf('e', 'd', 'a', 'b', 'c')
69-
}
70-
71-
"programs can be exchanged at positions" {
72-
mutableRingListOf("abcde").swap(3, 4).toJoinedString() shouldBe "abced"
73-
mutableRingListOf("abcde").swap(0, 4).toJoinedString() shouldBe "ebcda"
74-
mutableRingListOf("abcde").swap(3, 3).toJoinedString() shouldBe "abcde"
75-
}
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"programs can be exchanged by their name" {
78-
mutableRingListOf("abcde").swap('d', 'e').toJoinedString() shouldBe "abced"
79-
mutableRingListOf("abcde").swap('a', 'e').toJoinedString() shouldBe "ebcda"
80-
mutableRingListOf("abcde").swap('c', 'c').toJoinedString() shouldBe "abcde"
81-
}
82-
8315
"part 1: The order of the programs after their dance" {
8416
PermutationPromenade().doTheDance("abcde", input) shouldBe "baedc"
8517
PermutationPromenade().part1(input) shouldBe "paedcbfghijklmno"

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