From 4f0e9d7c7ca74dee9cb5d5a4b7a0de86e3da9bad Mon Sep 17 00:00:00 2001
From: dobiadi <50926840+dobiadi@users.noreply.github.com>
Date: Wed, 6 Dec 2023 21:23:56 +0100
Subject: [PATCH] Day4 Rust

---
 day4/rust/.gitignore  |  1 +
 day4/rust/Cargo.lock  |  7 ++++
 day4/rust/Cargo.toml  |  8 +++++
 day4/rust/src/main.rs | 84 +++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 100 insertions(+)
 create mode 100644 day4/rust/.gitignore
 create mode 100644 day4/rust/Cargo.lock
 create mode 100644 day4/rust/Cargo.toml
 create mode 100644 day4/rust/src/main.rs

diff --git a/day4/rust/.gitignore b/day4/rust/.gitignore
new file mode 100644
index 0000000..eb5a316
--- /dev/null
+++ b/day4/rust/.gitignore
@@ -0,0 +1 @@
+target
diff --git a/day4/rust/Cargo.lock b/day4/rust/Cargo.lock
new file mode 100644
index 0000000..b21cc6a
--- /dev/null
+++ b/day4/rust/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "rust"
+version = "0.1.0"
diff --git a/day4/rust/Cargo.toml b/day4/rust/Cargo.toml
new file mode 100644
index 0000000..1ec6963
--- /dev/null
+++ b/day4/rust/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "rust"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/day4/rust/src/main.rs b/day4/rust/src/main.rs
new file mode 100644
index 0000000..68c674c
--- /dev/null
+++ b/day4/rust/src/main.rs
@@ -0,0 +1,84 @@
+use std::collections::VecDeque;
+
+struct Card {
+    _id: usize,
+    winning_numbers: Vec<usize>,
+    scratched_numbers: Vec<usize>,
+}
+
+fn main() {
+    let stdin = std::io::stdin();
+
+    let mut cards = Vec::new();
+
+    for line in stdin.lines() {
+        let line = line.unwrap();
+
+        let (card_id_str, numbers) = line.split_once(':').unwrap();
+
+        let card_id = card_id_str
+            .split_once(' ')
+            .unwrap()
+            .1
+            .trim()
+            .parse()
+            .unwrap();
+
+        let (winning_numbers_str, scratched_numbers_str) = numbers.split_once('|').unwrap();
+
+        let winning_numbers = winning_numbers_str
+            .split(' ')
+            .filter(|e| e.len() > 0)
+            .map(|e| e.parse().unwrap())
+            .collect();
+
+        let scratched_numbers = scratched_numbers_str
+            .split(' ')
+            .filter(|e| e.len() > 0)
+            .map(|e| e.parse().unwrap())
+            .collect();
+
+        cards.push(Card {
+            _id: card_id,
+            winning_numbers,
+            scratched_numbers,
+        });
+    }
+
+    let mut part1 = 0;
+    let mut part2 = 0;
+
+    let mut foresight = VecDeque::new();
+
+    for card in &cards {
+        let mut score = 0;
+        let mut win_num = 0;
+
+        let card_num = foresight.pop_front().unwrap_or(0) + 1;
+        part2 += card_num;
+
+        for scratched_number in &card.scratched_numbers {
+            if card.winning_numbers.contains(&scratched_number) {
+                win_num += 1;
+                if score == 0 {
+                    score = 1;
+                } else {
+                    score *= 2;
+                }
+            }
+        }
+
+        for i in 0..win_num {
+            if let Some(n) = foresight.get(i) {
+                foresight[i] = n + card_num;
+            } else {
+                foresight.push_back(card_num);
+            }
+        }
+
+        part1 += score;
+    }
+
+    println!("{}", part1);
+    println!("{}", part2);
+}