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add ocaml to euclidean #11

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Sep 17, 2017
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add ocaml to euclidean #11

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23 changes: 23 additions & 0 deletions chapters/fundamental_algorithms/euclidean_algorithm/euclidean.md
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Expand Up @@ -331,3 +331,26 @@ fn main() {
println!("{}", chk2);
}
```

### OCaml

```ocaml
let rec euclid_mod a b =
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Can also be written as

let rec euclid_mod a = function
  | 0 -> a
  | b -> euclid_mod b (a mod b)

This also looks more like the Haskell version that uses patterns directly in equations.

if b = 0 then
a
else
euclid_mod b (a mod b)

let rec euclid_sub a b =
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Looks good, I'd condense it a little bit since the body is so narrow:

let rec euclid_sub a b =
  if a = b then a
  else if a < b then euclid_sub a (b - a)
  else euclid_sub (a - b) b

if a = b then
a
else if a < b then
euclid_sub a (b - a)
else
euclid_sub (a - b) b

let chk1 = euclid_mod (64 * 67) (64 * 81)
let chk2 = euclid_sub (128 * 12) (128 * 77)
let () = print_string ((int_of_string chk1) ^ "\n")
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Can use print_endline to avoid manually adding newlines, use pipe-forward, and also sequence into a single expression, i.e.

let () =
  chk1 |> int_of_string |> print_endline;
  chk2 |> int_of_string |> print_endline

let () = print_string ((int_of_string chk2) ^ "\n")
```