docs(2025d03p01): add implementation plan

1 files changed, 19 insertions, 0 deletions

diff --git a/2025/ocaml/lib/application/d03p01.ml b/2025/ocaml/lib/application/d03p01.ml
index 26319df..b63679e 100644
--- a/2025/ocaml/lib/application/d03p01.ml
+++ b/2025/ocaml/lib/application/d03p01.ml
@@ -1 +1,20 @@
+(** Day 3 Part 1
+   Implementation Plan:
+
+   For each line:
+   1. Start with the tuple [(None, None)]
+   2. Put the first two digits in the sequence into the tuple => [(Some m, Some n)]
+   3. Walk the sequence
+     - IF the digit in the sequence is greater than the first element of the tuple
+       AND we are not looking at the last digit in the sequence,
+         replace the first element of the tuple with that digit and set the other digit to None.
+     - IF the digit in the sequence did not replace the first element of the tuple
+       AND the digit is greater than the second element of the tuple,
+        replace the second element of the tuple with that digit.
+   4. Concat the elements of the tuple "string-wise" => [(Some m', Some n')] => [m' ^ n']
+   5. Cast to int
+
+   Sum the result of each line
+ *)
+
 let solve _ () = failwith "not started"