day01

src/days/d01.rs

@@ -1,10 +1,34 @@
-use std::collections::HashMap;
 use std::fs;
 
 pub fn solve() {
     let path = "res/01/input";
 
-    println!("Result 1: {}", 42);
+    let contents = fs::read_to_string(path).expect("Something went wrong reading the file");
 
-    println!("Result 2: {}", 42);
+    let mut numbers1 = Vec::<usize>::new();
+    let mut numbers2 = Vec::<usize>::new();
+
+    for line in contents.lines() {
+        let (n1, n2) = line.split_once("   ").unwrap();
+        numbers1.push(n1.parse::<usize>().unwrap());
+        numbers2.push(n2.parse::<usize>().unwrap());
+    }
+
+    numbers1.sort();
+    numbers2.sort();
+
+    let result: usize = numbers1
+        .iter()
+        .enumerate()
+        .map(|(i, n)| n.abs_diff(numbers2[i]))
+        .sum();
+
+    println!("Result 1: {}", result);
+
+    let result: usize = numbers1
+        .iter()
+        .map(|n| numbers2.iter().filter(|n2| n == *n2).count() * n)
+        .sum();
+
+    println!("Result 2: {}", result);
 }

src/main.rs

@@ -1,5 +1,4 @@
 pub mod days;
-#[macro_use]
 extern crate scan_fmt;
 
 use std::time::Instant;