Initial data commit

Task/Fibonacci-sequence/OCaml/fibonacci-sequence-6.ocaml

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+open List
+;;
+let rec bin n =
+  if n < 2 then [n mod 2 = 1]
+  else bin (n/2) @ [n mod 2 = 1]
+;;
+let cut = function
+  | [] -> []
+  | _ :: x -> x
+;;
+let multiply a b =
+  let ((p, q), (r, s)) = a in
+  let ((t, u), (v, w)) = b in
+  ((p*t+q*v, p*u+q*w), (r*t+s*v, r*u+s*w))
+;;
+let fib n =
+  let rec f p q r =
+    if length r = 1 then
+      if nth r 0 then (multiply p q, q)
+      else (p, q)
+    else
+      let (pp, qq) = f p q (cut r) in
+      let qqq = multiply qq qq in
+      if nth r 0 then (multiply pp qqq, qqq)
+      else (pp, qqq) in
+  f ((1L, 0L), (0L, 1L)) ((1L, 1L), (1L, 0L)) (bin n) |> fst |> fst |> snd
+;;