From eae96b74591c3f1d03980939f6ae3ff8d86f85ca Mon Sep 17 00:00:00 2001
From: Kevin Caffrey <kcaffrey@gmail.com>
Date: Sat, 16 Dec 2023 14:30:36 -0500
Subject: [PATCH] simply neighbors iterator after refactor for day 16

---
 README.md     |  4 ++--
 src/bin/16.rs | 10 ++++------
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/README.md b/README.md
index fa1b3dc..6cc065a 100644
--- a/README.md
+++ b/README.md
@@ -47,9 +47,9 @@ Solutions for [Advent of Code](https://adventofcode.com/) in [Rust](https://www.
 | [Day 13](./src/bin/13.rs) | `12.3µs` | `15.9µs` |
 | [Day 14](./src/bin/14.rs) | `25.0µs` | `4.5ms` |
 | [Day 15](./src/bin/15.rs) | `20.4µs` | `85.9µs` |
-| [Day 16](./src/bin/16.rs) | `223.2µs` | `10.9ms` |
+| [Day 16](./src/bin/16.rs) | `177.4µs` | `8.2ms` |
 
-**Total: 18.14ms**
+**Total: 15.39ms**
 <!--- benchmarking table --->
 
 ---
diff --git a/src/bin/16.rs b/src/bin/16.rs
index 134199d..e2bf85c 100644
--- a/src/bin/16.rs
+++ b/src/bin/16.rs
@@ -84,12 +84,10 @@ impl Grid {
         dir: Direction,
         tile: Tile,
     ) -> impl Iterator<Item = (Coordinate, Direction, Tile)> + '_ {
-        std::iter::once(tile.next(dir))
-            .flatten()
-            .filter_map(move |dir| {
-                self.move_in_dir(coord, dir)
-                    .map(|c| (c, dir, self.get_tile(c)))
-            })
+        tile.next(dir).filter_map(move |dir| {
+            self.move_in_dir(coord, dir)
+                .map(|c| (c, dir, self.get_tile(c)))
+        })
     }
 
     pub fn get_tile(&self, coord: Coordinate) -> Tile {