Initial data commit

Task/Variable-length-quantity/Scala/variable-length-quantity.scala

@@ -0,0 +1,27 @@
+object VlqCode {
+  def encode(x:Long)={
+    val result=scala.collection.mutable.Stack[Byte]()
+    result push (x&0x7f).toByte
+    var l = x >>> 7
+    while(l>0){
+      result push ((l&0x7f)|0x80).toByte
+      l >>>= 7
+    }
+    result.toArray
+  }
+
+  def decode(a:Array[Byte])=a.foldLeft(0L)((r, b) => r<<7|b&0x7f)
+
+  def toString(a:Array[Byte])=a map("%02x".format(_)) mkString("[", ", ", "]")
+
+  def test(x:Long)={
+    val enc=encode(x)
+    println("0x%x => %s => 0x%x".format(x, toString(enc), decode(enc)))
+  }
+
+  def main(args: Array[String]): Unit = {
+    val xs=Seq(0, 0x7f, 0x80, 0x2000, 0x3fff, 0x4000, 0x1FFFFF, 0x200000, 0x8000000,
+               0xFFFFFFF, 0xFFFFFFFFL, 0x842FFFFFFFFL, 0x0FFFFFFFFFFFFFFFL)
+    xs foreach test
+  }
+}