From 7a8b7c994e8cac68486fe6e053946c4dcd5a1e2c Mon Sep 17 00:00:00 2001
From: Antoine Martin <antoine@alarsyo.net>
Date: Fri, 17 Dec 2021 18:48:12 +0100
Subject: [PATCH] 2021: day17: improvement ideas

---
 aoc2021/src/day17.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/aoc2021/src/day17.rs b/aoc2021/src/day17.rs
index 8a0181a..1def61b 100644
--- a/aoc2021/src/day17.rs
+++ b/aoc2021/src/day17.rs
@@ -1,3 +1,10 @@
+//! Improvement ideas:
+//!
+//! X and Y coordinates are independant, so we can compute them separately, and keep track of which
+//! values of X and Y can ever reach the target area, and if so, keep the step numbers where they
+//! match. Some cross referencing can then isolate the valid trajectories.
+//!
+//! This already runs in 1ms though so... maybe later
 use std::cmp::Ordering;
 use std::fmt::Write;
 use std::ops::RangeInclusive;