ocaml: phase 5.1 anagram_check.ml baseline (char-frequency array, 2/4 anagrams)

to_counts builds a 256-slot int array of character frequencies:

  let to_counts s =
    let counts = Array.make 256 0 in
    for i = 0 to String.length s - 1 do
      let c = Char.code s.[i] in
      counts.(c) <- counts.(c) + 1
    done;
    counts

same_counts compares two arrays element-by-element via for loop +
bool ref. is_anagram composes them.

Four pairs:
  listen ~ silent       true
  hello !~ world        false
  anagram ~ nagaram     true
  abc !~ abcd           false (length differs)
  sum                   2

Exercises Array.make + arr.(i) + arr.(i) <- v + nested for loops +
Char.code + s.[i].

57 baseline programs total.

lib/ocaml/baseline/expected.json

@@ -1,5 +1,6 @@
 {
   "ackermann.ml": 125,
+  "anagram_check.ml": 2,
   "anagrams.ml": 3,
   "bag.ml": 3,
   "bigint_add.ml": 28,