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September 2017 Update

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Ingy döt Net 2017-09-23 10:01:46 +02:00
parent bba7bfd280
commit ba8067c3b7
14570 changed files with 153136 additions and 63871 deletions
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29
Task/Fibonacci-sequence/OCaml/fibonacci-sequence-2.ocaml
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@ -1,12 +1,19 @@
let rec fib_rec n =
if n < 2 then
n
else
fib_rec (n - 1) + fib_rec (n - 2)
open Num
(* with support for negatives *)
let rec fib = function
0 -> 0
| 1 -> 1
| n -> if n > 0 then fib (n-1) + fib (n-2)
else fib (n+2) - fib (n+1)
let fib =
let rec fib_aux f0 f1 = function
| 0 -> f0
| 1 -> f1
| n -> fib_aux f1 (f1 +/ f0) (n - 1)
in
fib_aux (num_of_int 0) (num_of_int 1)
(* support for negatives *)
let fib n =
if n < 0 && n mod 2 = 0 then minus_num (fib (abs n))
else fib (abs n)
;;
(* It can be called from the command line with an argument *)
(* Result is send to standart output *)
let n = int_of_string Sys.argv.(1) in
print_endline (string_of_num (fib n))