From fceda8ac1b6b00727b1b1b8e4cdc5078e59c73a2 Mon Sep 17 00:00:00 2001
From: Antoine Martin <antoine@alarsyo.net>
Date: Mon, 6 Dec 2021 11:53:34 +0100
Subject: [PATCH] 2021: day06: use rotate_left

---
 aoc2021/src/day06.rs | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/aoc2021/src/day06.rs b/aoc2021/src/day06.rs
index 3fae107..499531b 100644
--- a/aoc2021/src/day06.rs
+++ b/aoc2021/src/day06.rs
@@ -38,12 +38,9 @@ impl School {
     fn next_turn(&mut self) {
         let newly_spawned = self.fish_timers[0];
 
-        for i in 1..self.fish_timers.len() {
-            self.fish_timers[i - 1] = self.fish_timers[i];
-        }
+        self.fish_timers.rotate_left(1);
 
         self.fish_timers[SPAWNING_DELAY - 1] += newly_spawned;
-        *self.fish_timers.last_mut().unwrap() = newly_spawned;
     }
 
     fn size(&self) -> usize {