From 6a8ea1b39211f4db45d718cc10d3a0d244cf6829 Mon Sep 17 00:00:00 2001
From: Florent DENEF <fdenef@aneo.fr>
Date: Thu, 29 Dec 2022 13:55:39 +0100
Subject: [PATCH] Day - part 1 done hehehe

---
 Cargo.toml   |  1 -
 src/prob6.rs | 60 +++++++---------------------------------------------
 2 files changed, 8 insertions(+), 53 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index 2a90492..bf7e11d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,4 +13,3 @@ rpath = true
 [dependencies]
 nom = "7.1.1"
 itertools = "0.10.5"
-fancy-regex = { version = "0.10.0", features = ["perf-literal", "perf-dfa", "perf-inline", "perf-cache"] }
diff --git a/src/prob6.rs b/src/prob6.rs
index a713d5e..7705414 100644
--- a/src/prob6.rs
+++ b/src/prob6.rs
@@ -1,57 +1,13 @@
-use std::collections::HashSet;
+use itertools::Itertools;
 
-use fancy_regex::Regex;
-
-/// Tries to find the 4 character match.
-///
-/// # Arguments
-///
-/// * `datagram`:
-///
-/// returns: ()
-///
-/// # Examples
-///
-/// ```
-///
-/// ```
-fn begin_datagram(datagram: &str) {
-    let mut letters = HashSet::<char>::new();
-    let primary_iter = datagram.chars().fuse();
-    let mut motif_iter = primary_iter.clone();
-    while letters.len() < 4 {
-        if let Some(tmp) = motif_iter.next() {
-            if !letters.insert(tmp) {
-                letters.clear();
-            }
-        } else {
-            break;
-        }
-    }
+fn begin_datagram(datagram: &str, size: usize) -> usize {
+    size + datagram
+        .as_bytes()
+        .windows(size)
+        .position(|window| window.iter().tuple_combinations().all(|(a, b)| a != b))
+        .unwrap()
 }
 
 pub fn solve_part1(content: &str) -> i32 {
-    let _content = content;
-    return match Regex::new(r"^(?:([A-Za-z])(?!.*\1))*$") {
-        Ok(_reg) => {
-            println!("Regex is built.");
-            match _reg.find(_content) {
-                Ok(matches) => {
-                    if let Some(yay) = matches {
-                        println!("{}", yay.as_str());
-                    } else {
-                        println!("Snif no match :(");
-                    }
-                }
-                Err(err) => {
-                    eprintln!("{err}")
-                }
-            }
-            0
-        }
-        Err(err) => {
-            eprintln!("{err}");
-            0
-        }
-    };
+    begin_datagram(content, 4) as i32
 }