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Merged
harry0000 merged 1 commit into from
Oct 21, 2025
Merged

Unify and rename generic string algorithms #40

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15 changes: 10 additions & 5 deletions src/main/scala/io/github/acl4s/String.scala
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Original file line number Diff line number Diff line change
@@ -1,5 +1,7 @@
package io.github.acl4s

import scala.annotation.targetName

import io.github.acl4s.internal.foreach

def suffixArray(s: Array[Int], upper: Int): Array[Int] = {
Expand All @@ -8,7 +10,8 @@ def suffixArray(s: Array[Int], upper: Int): Array[Int] = {
internal.saIs(s.clone(), upper)
}

def suffixArrayArbitrary[T](s: Array[T])(using Ordering[T]): Array[Int] = {
@targetName("suffixArrayArbitrary")
def suffixArray[T](s: Array[T])(using Ordering[T]): Array[Int] = {
import scala.math.Ordered.orderingToOrdered

val n = s.length
Expand Down Expand Up @@ -37,7 +40,8 @@ def suffixArray(s: String): Array[Int] = {
* T. Kasai, G. Lee, H. Arimura, S. Arikawa, and K. Park,
* Linear-Time Longest-Common-Prefix Computation in Suffix Arrays and Its Applications
*/
def lcpArrayArbitrary[T](s: Array[T], sa: Array[Int]): Array[Int] = {
@targetName("lcpArrayArbitrary")
def lcpArray[T](s: Array[T], sa: Array[Int]): Array[Int] = {
require(s.length == sa.length)
val n = s.length
require(n >= 1)
Expand Down Expand Up @@ -65,7 +69,7 @@ def lcpArrayArbitrary[T](s: Array[T], sa: Array[Int]): Array[Int] = {
}

def lcpArray(s: String, sa: Array[Int]): Array[Int] = {
lcpArrayArbitrary(s.toCharArray.map(_.toInt), sa)
lcpArray(s.toCharArray.map(_.toInt), sa)
}

/**
Expand All @@ -74,7 +78,8 @@ def lcpArray(s: String, sa: Array[Int]): Array[Int] = {
* Algorithms on Strings, Trees, and Sequences: Computer Science and
* Computational Biology
*/
private def zAlgorithmImpl[T](s: Array[T]): Array[Int] = {
@targetName("zAlgorithmArbitrary")
def zAlgorithm[T](s: Array[T]): Array[Int] = {
val n = s.length
if (n == 0) {
return Array.empty
Expand All @@ -98,4 +103,4 @@ private def zAlgorithmImpl[T](s: Array[T]): Array[Int] = {
z
}

def zAlgorithm(s: String): Array[Int] = zAlgorithmImpl(s.toCharArray)
def zAlgorithm(s: String): Array[Int] = zAlgorithm(s.toCharArray)
48 changes: 24 additions & 24 deletions src/test/scala/io/github/acl4s/StringSuite.scala
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Original file line number Diff line number Diff line change
Expand Up @@ -82,16 +82,16 @@ class StringSuite extends munit.FunSuite {

test("suffixArray empty") {
assertEquals(suffixArray("").toSeq, Seq.empty[Int])
assertEquals(suffixArrayArbitrary(Array.empty[Int]).toSeq, Seq.empty[Int])
assertEquals(suffixArrayArbitrary(Array.empty[Long]).toSeq, Seq.empty[Int])
assertEquals(suffixArray(Array.empty[Int]).toSeq, Seq.empty[Int])
assertEquals(suffixArray(Array.empty[Long]).toSeq, Seq.empty[Int])
}

test("suffixArray single") {
assertEquals(suffixArrayArbitrary(Array(0)).toSeq, Seq(0))
assertEquals(suffixArrayArbitrary(Array(-1)).toSeq, Seq(0))
assertEquals(suffixArrayArbitrary(Array(1)).toSeq, Seq(0))
assertEquals(suffixArrayArbitrary(Array(Int.MinValue)).toSeq, Seq(0))
assertEquals(suffixArrayArbitrary(Array(Int.MaxValue)).toSeq, Seq(0))
assertEquals(suffixArray(Array(0)).toSeq, Seq(0))
assertEquals(suffixArray(Array(-1)).toSeq, Seq(0))
assertEquals(suffixArray(Array(1)).toSeq, Seq(0))
assertEquals(suffixArray(Array(Int.MinValue)).toSeq, Seq(0))
assertEquals(suffixArray(Array(Int.MaxValue)).toSeq, Seq(0))
}

test("suffixArray SALCP naive") {
Expand All @@ -112,9 +112,9 @@ class StringSuite extends munit.FunSuite {

val sa = suffixArrayNaive(s)

assertEquals(suffixArrayArbitrary(s).toSeq, sa.toSeq)
assertEquals(suffixArray(s).toSeq, sa.toSeq)
assertEquals(suffixArray(s, maxC).toSeq, sa.toSeq)
assertEquals(lcpArrayArbitrary(s, sa).toSeq, lcpArrayNaive(s, sa).toSeq)
assertEquals(lcpArray(s, sa).toSeq, lcpArrayNaive(s, sa).toSeq)
}
}
for (n <- 1 to 10) {
Expand All @@ -134,17 +134,17 @@ class StringSuite extends munit.FunSuite {

val sa = suffixArrayNaive(s)

assertEquals(suffixArrayArbitrary(s).toSeq, sa.toSeq)
assertEquals(suffixArray(s).toSeq, sa.toSeq)
assertEquals(suffixArray(s, maxC).toSeq, sa.toSeq)
assertEquals(lcpArrayArbitrary(s, sa).toSeq, lcpArrayNaive(s, sa).toSeq)
assertEquals(lcpArray(s, sa).toSeq, lcpArrayNaive(s, sa).toSeq)
}
}
}

test("suffixArray all A test") {
for (n <- 1 to 100) {
val s = Array.fill(n)(10)
assertEquals(suffixArrayArbitrary(s).toSeq, suffixArrayNaive(s).toSeq)
assertEquals(suffixArray(s).toSeq, suffixArrayNaive(s).toSeq)
assertEquals(suffixArray(s, 10).toSeq, suffixArrayNaive(s).toSeq)
assertEquals(suffixArray(s, 12).toSeq, suffixArrayNaive(s).toSeq)
}
Expand All @@ -153,12 +153,12 @@ class StringSuite extends munit.FunSuite {
test("suffixArray all AB test") {
for (n <- 1 to 100) {
val s = Array.tabulate(n)(_ % 2)
assertEquals(suffixArrayArbitrary(s).toSeq, suffixArrayNaive(s).toSeq)
assertEquals(suffixArray(s).toSeq, suffixArrayNaive(s).toSeq)
assertEquals(suffixArray(s, 3).toSeq, suffixArrayNaive(s).toSeq)
}
for (n <- 1 to 100) {
val s = Array.tabulate(n)(i => 1 - (i % 2))
assertEquals(suffixArrayArbitrary(s).toSeq, suffixArrayNaive(s).toSeq)
assertEquals(suffixArray(s).toSeq, suffixArrayNaive(s).toSeq)
assertEquals(suffixArray(s, 3).toSeq, suffixArrayNaive(s).toSeq)
}
}
Expand Down Expand Up @@ -198,11 +198,11 @@ class StringSuite extends munit.FunSuite {
val lcp = lcpArray(s, sa).toSeq
assertEquals(lcp, Seq(1, 0))

assertEquals(lcpArrayArbitrary(Array(0, 0, 1), sa).toSeq, lcp)
assertEquals(lcpArrayArbitrary(Array(-100, -100, 100), sa).toSeq, lcp)
assertEquals(lcpArrayArbitrary(Array(Byte.MinValue, Byte.MinValue, Byte.MaxValue), sa).toSeq, lcp)
assertEquals(lcpArrayArbitrary(Array(Int.MinValue, Int.MinValue, Int.MaxValue), sa).toSeq, lcp)
assertEquals(lcpArrayArbitrary(Array(Long.MinValue, Long.MinValue, Long.MaxValue), sa).toSeq, lcp)
assertEquals(lcpArray(Array(0, 0, 1), sa).toSeq, lcp)
assertEquals(lcpArray(Array(-100, -100, 100), sa).toSeq, lcp)
assertEquals(lcpArray(Array(Byte.MinValue, Byte.MinValue, Byte.MaxValue), sa).toSeq, lcp)
assertEquals(lcpArray(Array(Int.MinValue, Int.MinValue, Int.MaxValue), sa).toSeq, lcp)
assertEquals(lcpArray(Array(Long.MinValue, Long.MinValue, Long.MaxValue), sa).toSeq, lcp)
}

private def zAlgorithmNaive[T](s: Array[T]): Array[Int] = {
Expand All @@ -218,7 +218,7 @@ class StringSuite extends munit.FunSuite {

test("zAlgorithm empty") {
assertEquals(zAlgorithm("").toSeq, Seq.empty[Int])
assertEquals(zAlgorithmImpl(Array.empty[Int]).toSeq, Seq.empty[Int])
assertEquals(zAlgorithm(Array.empty[Int]).toSeq, Seq.empty[Int])
}

test("zAlgorithm simple") {
Expand All @@ -241,8 +241,8 @@ class StringSuite extends munit.FunSuite {
assertEquals(lcp.toSeq, Seq(9, 0, 7, 0, 5, 0, 3, 0, 1))
}

assertEquals(zAlgorithmImpl(Array(1, 10, 1, 10)).toSeq, Seq(4, 0, 2, 0))
assertEquals(zAlgorithmImpl(Array(0, 0, 0, 0, 0, 0, 0)).toSeq, zAlgorithmNaive(Array(0, 0, 0, 0, 0, 0, 0)).toSeq)
assertEquals(zAlgorithm(Array(1, 10, 1, 10)).toSeq, Seq(4, 0, 2, 0))
assertEquals(zAlgorithm(Array(0, 0, 0, 0, 0, 0, 0)).toSeq, zAlgorithmNaive(Array(0, 0, 0, 0, 0, 0, 0)).toSeq)
}

test("zAlgorithm naive") {
Expand All @@ -255,7 +255,7 @@ class StringSuite extends munit.FunSuite {
s(i) = g % 4
g /= 4
}
assertEquals(zAlgorithmImpl(s).toSeq, zAlgorithmNaive(s).toSeq)
assertEquals(zAlgorithm(s).toSeq, zAlgorithmNaive(s).toSeq)
}
}
for (n <- 1 to 10) {
Expand All @@ -267,7 +267,7 @@ class StringSuite extends munit.FunSuite {
s(i) = g % 2
g /= 2
}
assertEquals(zAlgorithmImpl(s).toSeq, zAlgorithmNaive(s).toSeq)
assertEquals(zAlgorithm(s).toSeq, zAlgorithmNaive(s).toSeq)
}
}
}
Expand Down