35 lines
862 B
Kotlin
35 lines
862 B
Kotlin
package com.infendro.random.prng
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import com.infendro.bytearray.padStart
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import com.infendro.bytearray.toUByteArray
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import com.infendro.bytearray.toULong
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import kotlin.math.min
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import kotlin.properties.Delegates
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class LCG internal constructor() : PRNG() {
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private val a: ULong = 25214903917UL
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private val c: ULong = 11UL
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private val m: ULong = 1UL shl 48
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private var x: ULong by Delegates.notNull()
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override fun seed(
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seed: UByteArray,
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) {
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val s = seed.padStart(8, 0x00U).takeLast(8).toUByteArray()
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x = s.toULong() % m
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}
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override fun generate(
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count: Int,
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): UByteArray {
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return buildList {
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while (size < count) {
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x = (a * x + c) % m
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addAll(x.toUByteArray().takeLast(min(count - size, 6)))
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}
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}.toUByteArray()
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}
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}
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