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@file:kotlin.jvm.JvmMultifileClass
@file:kotlin.jvm.JvmName("ArraysKt")


package kotlin

import java.util.*

/**
 * Returns an array with the specified [size], where each element is calculated by calling the specified
 * [init] function. The `init` function returns an array element given its index.
 */
public inline fun  Array(size: Int, init: (Int) -> T): Array {
    val result = arrayOfNulls(size)

    for (i in 0..size - 1) {
        result[i] = init(i)
    }

    return result as Array
}

/**
 * Returns an empty array of the specified type [T].
 */
public inline fun  emptyArray(): Array = arrayOfNulls(0) as Array

/**
 * Returns a single list of all elements from all arrays in the given array.
 */
public fun  Array>.flatten(): List {
    val result = ArrayList(sumBy { it.size() })
    for (element in this) {
        result.addAll(element)
    }
    return result
}

/**
 * Returns a pair of lists, where
 * *first* list is built from the first values of each pair from this array,
 * *second* list is built from the second values of each pair from this array.
 */
public fun  Array>.unzip(): Pair, List> {
    val listT = ArrayList(size())
    val listR = ArrayList(size())
    for (pair in this) {
        listT.add(pair.first)
        listR.add(pair.second)
    }
    return listT to listR
}