initial commit

day5/.gitignore

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+/target

day5/Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "day5"
+version = "0.1.0"

day5/Cargo.toml

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+[package]
+name = "day5"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

day5/src/main.rs

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+use std::fs::File;
+use std::io::{self, BufRead};
+
+fn main() {
+    let file = File::open("input").unwrap();
+
+    let mut orderings: Vec<(i64, i64)> = Vec::new();
+    let mut updates: Vec<Vec<i64>> = Vec::new();
+    
+    for line_result in io::BufReader::new(file).lines() {
+        let line = match line_result {
+            Ok(content) => content,
+            Err(e) => {
+                eprintln!("Error reading line: {}", e);
+                continue;
+            }
+        };
+        if line.contains("|") {
+            let pages: Vec<_> = line.split("|").collect();
+            orderings.push(
+                (
+                    pages[0].parse::<i64>().unwrap(),
+                    pages[1].parse::<i64>().unwrap()
+                )
+            )
+        }
+        else if line.contains(",") {
+            updates.push(line.split(",").map(|p| p.parse::<i64>().unwrap()).collect());
+        }
+        else {
+            println!("unexpected input: '{}'", line)
+        }
+    }
+
+    let mut sum_correct: i64 = 0;
+    let mut sum_reordered: i64 = 0;
+    for update in updates {
+        let mut is_correct = true;
+        'update: for i in 1..update.len() {
+            for (p1, p2) in orderings.clone().into_iter() {
+                if update[i] == p1 && update[i-1] == p2 {
+                    is_correct = false;
+                    break 'update
+                }
+            }
+        }
+        if is_correct {
+            sum_correct += update[(update.len()-1)/2];
+        }
+        else {
+
+            sum_reordered += update[(update.len()-1)/2];
+        }
+    }
+
+    println!("Sum (correct): {}", sum_correct);
+    println!("Sum (reordered): {}", sum_reordered);
+}
+