example to pass tests, with test change to allow negative numbers

Author: TheRealOwenRees

exercises/practice/perfect-numbers/.meta/example.ml

@@ -1,3 +1,21 @@
 let classify n = 
-  if n < 1 then 
-    Error "Classification is only possible for positive integers."
+  let aliquot = function
+    | 1 -> 0
+    | n when n > 1 ->
+        let rec sum_factors acc factor =
+          if factor > n / 2 then acc
+          else if n mod factor = 0 then
+            sum_factors (acc + factor) (factor + 1)
+          else
+            sum_factors acc (factor + 1)
+        in
+        sum_factors 0 1
+    | _ -> 0 
+  in
+  match n with
+  | _ when n < 1 -> Error "Classification is only possible for positive integers."
+  | n -> 
+      let aliquot_sum = aliquot n in
+      if aliquot_sum = n then Ok "perfect"
+      else if aliquot_sum > n then Ok "abundant"
+      else Ok "deficient"

exercises/practice/perfect-numbers/test.ml

@@ -9,31 +9,31 @@ let ae exp got _test_ctxt = assert_equal ~printer:option_printer exp got
 
 let tests = [
   "Smallest perfect number is classified correctly" >::
-  ae (Ok "perfect") (classify 6);
+  ae (Ok "perfect") (classify (6));
   "Medium perfect number is classified correctly" >::
-  ae (Ok "perfect") (classify 28);
+  ae (Ok "perfect") (classify (28));
   "Large perfect number is classified correctly" >::
-  ae (Ok "perfect") (classify 33550336);
+  ae (Ok "perfect") (classify (33550336));
   "Smallest abundant number is classified correctly" >::
-  ae (Ok "abundant") (classify 12);
+  ae (Ok "abundant") (classify (12));
   "Medium abundant number is classified correctly" >::
-  ae (Ok "abundant") (classify 30);
+  ae (Ok "abundant") (classify (30));
   "Large abundant number is classified correctly" >::
-  ae (Ok "abundant") (classify 33550335);
+  ae (Ok "abundant") (classify (33550335));
   "Smallest prime deficient number is classified correctly" >::
-  ae (Ok "deficient") (classify 2);
+  ae (Ok "deficient") (classify (2));
   "Smallest non-prime deficient number is classified correctly" >::
-  ae (Ok "deficient") (classify 4);
+  ae (Ok "deficient") (classify (4));
   "Medium deficient number is classified correctly" >::
-  ae (Ok "deficient") (classify 32);
+  ae (Ok "deficient") (classify (32));
   "Large deficient number is classified correctly" >::
-  ae (Ok "deficient") (classify 33550337);
+  ae (Ok "deficient") (classify (33550337));
   "Edge case (no factors other than itself) is classified correctly" >::
-  ae (Ok "deficient") (classify 1);
+  ae (Ok "deficient") (classify (1));
   "Zero is rejected (as it is not a positive integer)" >::
-  ae (Error "Classification is only possible for positive integers.") (classify 0);
+  ae (Error "Classification is only possible for positive integers.") (classify (0));
   "Negative integer is rejected (as it is not a positive integer)" >::
-  ae (Error "Classification is only possible for positive integers.") (classify -1);
+  ae (Error "Classification is only possible for positive integers.") (classify (-1));
 ]
 
 let () =

templates/perfect-numbers/test.ml.tpl

@@ -11,7 +11,7 @@ let tests = [
   {{#cases}}
     {{#cases}}
       "{{description}}" >::
-        ae {{#input}}{{{expected}}} (classify {{{number}}}){{/input}};
+        ae {{#input}}{{{expected}}} (classify ({{number}})){{/input}};
     {{/cases}}
   {{/cases}}
 ]