2025 - Day 1 part 2 - rust

2025/rust1_2/src/main.rs

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+use std::fs::File;
+use std::io::{BufRead, BufReader};
+
+fn main() {
+    // let filename = "../1/input_example.txt";
+    let filename = "../1/input.txt";
+    let file = BufReader::new(File::open(filename).expect("Unable to open file"));
+
+    let mut dial: i32 = 50;
+    let mut count: i32 = 0;
+
+    for line in file.lines() {
+        let mut wline: String = line.unwrap();
+        let direction = wline.chars().next().unwrap();
+
+        wline.remove(0);
+        let distance: i32 = wline.parse().unwrap();
+        let was_zero: i32;
+
+        if direction == 'L' {
+            if dial == 0 {
+                was_zero = 0;
+            } else {
+                was_zero = 1;
+            }
+            dial -= distance;
+            if dial <= 0 {
+                count += (dial / 100).abs() + was_zero;
+            }
+            println!("Left distance={} dial={} count={}", distance, dial, count);
+        } else {
+            dial += distance;
+            if dial > 99 {
+                count += dial / 100;
+            }
+            println!("Right distance={} dial={} count={}", distance, dial, count);
+        }
+
+        dial = dial.rem_euclid(100)
+    }
+    println!("count: {}\n", count)
+}