Just another update

Task/Fibonacci-sequence/Scala/fibonacci-sequence-3.scala

@@ -1,4 +1,5 @@
-def fib(i:Int, a:Int=1, b:Int=0):Int = i match{
-    case 1 => b
-    case _ => fib(i-1, b, a+b)
-}
+def fib(x:Int, prev: BigInt = 0, next: BigInt = 1):BigInt = x match {
+    case 0 => prev
+    case 1 => next
+    case _ => fib(x-1, next, (next + prev))
+ }

Task/Fibonacci-sequence/Scala/fibonacci-sequence-5.scala

@@ -1,13 +1,3 @@
-// Fibonacci using BigInt with Stream.foldLeft optimized for GC (Scala v2.9 and above)
-// Does not run out of memory for very large Fibonacci numbers
-def fib(n:Int) = {
-
-  def series(i:BigInt,j:BigInt):Stream[BigInt] = i #:: series(j, i+j)
-
-  series(1,0).take(n).foldLeft(BigInt("0"))(_+_)
-}
-
-// Small test
-(0 to 13) foreach {n => print(fib(n).toString + " ")}
-
-// result: 0 1 1 2 3 5 8 13 21 34 55 89 144 233
+val it = Iterator.iterate((0,1)){case (a,b) => (b,a+b)}.map(_._1)
+//example:
+println(it.take(13).mkString(",")) //prints: 0,1,1,2,3,5,8,13,21,34,55,89,144