28 lines
744 B
Scala
28 lines
744 B
Scala
object VlqCode {
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def encode(x:Long)={
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val result=scala.collection.mutable.Stack[Byte]()
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result push (x&0x7f).toByte
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var l = x >>> 7
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while(l>0){
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result push ((l&0x7f)|0x80).toByte
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l >>>= 7
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}
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result.toArray
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}
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def decode(a:Array[Byte])=a.foldLeft(0L)((r, b) => r<<7|b&0x7f)
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def toString(a:Array[Byte])=a map("%02x".format(_)) mkString("[", ", ", "]")
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def test(x:Long)={
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val enc=encode(x)
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println("0x%x => %s => 0x%x".format(x, toString(enc), decode(enc)))
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}
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def main(args: Array[String]): Unit = {
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val xs=Seq(0, 0x7f, 0x80, 0x2000, 0x3fff, 0x4000, 0x1FFFFF, 0x200000, 0x8000000,
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0xFFFFFFF, 0xFFFFFFFFL, 0x842FFFFFFFFL, 0x0FFFFFFFFFFFFFFFL)
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xs foreach test
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}
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}
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