$inc fvmstd.fp

proc fib
  if dup 0 == then
    drop 0 return
  endif
  if dup 1 == then
    drop 1 return
  endif
  
  dup
  1 u- :fib
  swap
  2 u- :fib
  u+
endproc

proc main
  "Idx: " :puts :getuint
  :fib :putuint
endproc