From 2249b4b9ef9c9a5b5edfaecaf9c68339870260f8 Mon Sep 17 00:00:00 2001
From: Daniel Seiller <earthnuker@gmail.com>
Date: Wed, 9 Dec 2020 19:15:11 +0100
Subject: [PATCH] Day 9, faster

---
 src/day9.rs | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/day9.rs b/src/day9.rs
index 8204ed6..4e726b5 100644
--- a/src/day9.rs
+++ b/src/day9.rs
@@ -35,7 +35,7 @@ pub fn solve_part1(input: &Vec<usize>) -> usize {
     panic!("No match found!");
 }
 
-#[aoc(day9, part2)]
+#[aoc(day9, part2,bruteforce)]
 pub fn solve_part2(input: &Vec<usize>) -> usize {
     let inv_num = solve_part1(input);
     for start in 0..input.len() {
@@ -48,3 +48,14 @@ pub fn solve_part2(input: &Vec<usize>) -> usize {
     }
     panic!("No match found!");
 }
+
+#[aoc(day9, part2,faster)]
+pub fn solve_part2_fast(input: &Vec<usize>) -> usize {
+    let target_num = solve_part1(input);
+    for i in 2..=input.len() {
+        if let Some(w) = input.windows(i).find(|w| target_num==w.iter().sum()) {
+            return w.iter().max().unwrap()+w.iter().min().unwrap();
+        }
+    }
+    panic!("No match found!");
+}