Artifact 7393550d9bf36126324a2ec483c7c65711392411

File rosetta_code/fibonacci_sequence.rx part of check-in [b8db9be2b9] - more examples from rosetta code by crc on 2011-04-10 17:25:10. [annotate]

Recursive

: fib ( n-m ) dup [ 0 = ] [ 1 = ] bi or if; [ 1- fib ] sip [ 2 - fib ] do + ;


Iterative

2 elements previous result
: fib ( n-m )
  -1 !previous 1 !result
   1+ [ @result @previous over + !result !previous ] times @result ;