Fibonnaci Sequence fast implementation

Posted by user2947615 on Stack Overflow See other posts from Stack Overflow or by user2947615
Published on 2013-11-05T21:24:27Z Indexed on 2013/11/05 21:53 UTC
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scala

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fibonacci

I have written this function in Scala to calculate the fibonacci number given a particular index n:

 def fibonacci(n: Long): Long = {
 if(n <= 1) n
 else
   fibonacci(n - 1) + fibonacci(n - 2)     
}

However it is not efficient when calculating with large indexes. Therefore I need to implement a function using a tuple and this function should return two consecutive values as the result.

Can somebody give me any hints about this? I have never used Scala before. Thanks!

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