Day 1 Part 1 done, working on Part 2

advent_of_code_2025/src/day1/part1.rs

@@ -1,4 +1,32 @@
-
 pub fn solve(input: &str) {
-    
-}
+    let instructions = input
+        .lines()
+        .map(|str| {
+            let distance = str.chars().next().map(|ch| &str[ch.len_utf8()..]).unwrap().parse::<i32>().unwrap();
+            if str.starts_with('L') { -distance } else { distance }
+        })
+        .collect::<Vec<_>>();
+
+    let mut counter = 0;
+    let mut dial = 50;
+
+    for instruction in instructions {
+        dial += instruction;
+
+        match dial {
+            ..=-1 => {
+                dial += 100 * (dial / -100);
+            }
+            100.. => {
+                dial %= 100;
+            }
+            _ => {}
+        }
+
+        if dial == 0 {
+            counter += 1;
+        }
+    }
+
+    println!("part 1 counter: {}", counter);
+}

advent_of_code_2025/src/day1/part2.rs

@@ -1,4 +1,44 @@
 
 pub fn solve(input: &str) {
-    
+    let instructions = input.lines().map(|str| {
+        let distance = unsafe { str::from_utf8_unchecked( &str.bytes().collect::<Vec<_>>()[1..]).parse::<i32>().unwrap() };
+        if str.bytes().next().unwrap() == b'L' {
+            -distance
+        } else {
+            distance
+        }
+    }).collect::<Vec<_>>();
+
+    let mut counter = 0;
+    let mut dial = 50;
+
+    println!("instr min: {}, max: {}", instructions.iter().min().unwrap(), instructions.iter().max().unwrap());
+
+    for instruction in instructions {
+        // let old = dial;
+        // let new = dial + instruction;
+        
+        dial += instruction;
+
+        match dial {
+            ..=-1 => {
+                counter += dial / -100; 
+                dial += 100 * (dial / -100); },
+            100.. => { 
+                counter += dial / 100;
+                dial %= 100;
+            },
+            _ => {}
+        }
+
+        // println!("{old} -> {new} = {dial}");
+
+        if dial == 0 {
+            // println!("incremented!");
+            counter += 1;
+        }
+    }
+
+    println!("counter: {}", counter);
+
 }

advent_of_code_2025/src/day1/test.txt

@@ -0,0 +1,10 @@
+L68
+L30
+R48
+L5
+R60
+L55
+L1
+L99
+R14
+L82

advent_of_code_2025/src/main.rs

@@ -1,4 +1,5 @@
 use paste::paste;
 mod utility;
 
-solve_day!{1}
+// solve_day!{1}
+test_day!{1}