From b3d780a4dba7edc1cbd151528d36761e936c4ce8 Mon Sep 17 00:00:00 2001
From: Leah Neukirchen <leah@vuxu.org>
Date: Thu, 6 Dec 2018 15:57:53 +0100
Subject: day05

---
 day05.rs | 31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)
 create mode 100644 day05.rs

(limited to 'day05.rs')

diff --git a/day05.rs b/day05.rs
new file mode 100644
index 0000000..ea6e919
--- /dev/null
+++ b/day05.rs
@@ -0,0 +1,31 @@
+use std::fs::File;
+use std::io::prelude::*;
+
+fn react(s: &mut String) -> usize {
+    while let Some(pos) = (0..s.len() - 1).find(|i| {
+        (s.as_bytes()[*i] as i32 - s.as_bytes()[*i + 1] as i32).abs() == 32
+    }) {
+        s.replace_range(pos..pos + 2, "");
+    }
+    return s.len();
+}
+
+fn main() {
+    let mut f = File::open("day05").unwrap();
+
+    let mut s = String::new();
+    f.read_to_string(&mut s).unwrap();
+    s.pop();
+
+    println!("{}", react(&mut s.clone()));
+
+    println!("{}",
+             (65u8..65u8 + 27)
+             .map(|c| {
+                 let mut t = s.clone();
+                 t.retain(|b| b != (c as char) && b != (c + 32u8) as char);
+                 react(&mut t)
+             })
+             .min()
+             .unwrap());
+}
-- 
cgit 1.4.1