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Как преобразовать ByteArray в ULong в kotlin.

 val byteArray = byteArrayOf(
    0, 0, 0, 0,
    0, 0, 0, 1
)
 

 fun UByteArray.getULongBe() =
    ((this[7].toULong() and 0xFFu) shl 56) or
            ((this[6].toULong() and 0xFFu) shl 48) or
            ((this[5].toULong() and 0xFFu) shl 40) or
            ((this[4].toULong() and 0xFFu) shl 32) or
            ((this[3].toULong() and 0xFFu) shl 24) or
            ((this[2].toULong() and 0xFFu) shl 16) or
            ((this[1].toULong() and 0xFFu) shl 8) or
            (this[0].toULong() and 0xFFu)

fun UByteArray.getULongLe() =
    ((this[0].toULong() and 0xFFu) shl 56) or
            ((this[1].toULong() and 0xFFu) shl 48) or
            ((this[2].toULong() and 0xFFu) shl 40) or
            ((this[3].toULong() and 0xFFu) shl 32) or
            ((this[4].toULong() and 0xFFu) shl 24) or
            ((this[5].toULong() and 0xFFu) shl 16) or
            ((this[6].toULong() and 0xFFu) shl 8) or
            (this[7].toULong() and 0xFFu)

val uByteArray = ubyteArrayOf(
    UByte.MAX_VALUE, UByte.MAX_VALUE,
    UByte.MAX_VALUE, UByte.MAX_VALUE,
    UByte.MAX_VALUE, UByte.MAX_VALUE,
    UByte.MAX_VALUE, UByte.MAX_VALUE,
)

ULong.MAX_VALUE 
// 18446744073709551615

uByteArray.getULongBe()
// 18446744073709551615
uByteArray.getULongLe()
// 18446744073709551615

val byteArray = byteArrayOf(
    0, 0, 0, 0,
    0, 0, 0, 1
)

byteArray.toUByteArray().getULongLe()
// 1
byteArray.toUByteArray().getULongBe()
// 72057594037927936