fixed day 10

day10/src/main.rs

@@ -1,5 +1,3 @@
-use std::collections::HashMap;
-
 fn main() {
     let input = "3113322113";
 
@@ -9,37 +7,35 @@ fn main() {
 fn part1(input: &str) {
     let mut input: Vec<_> = input.to_string().chars().collect();
 
-    for _ in 0..34 {
-        input = recurse(input);
+    for _ in 0..50 {
+        input = solve(input);
     }
-    for c in input {
-        print!("{c}");
-    }
-    println!();
+    println!("{}", input.len());
 }
 
-fn recurse(input: Vec<char>) -> Vec<char> {
-    if input.is_empty() {
-        return input;
-    }
+fn solve(input: Vec<char>) -> Vec<char> {
+    let mut result = vec![];
 
-    let mut iter = input.iter();
-    let first_digit = *iter.next().unwrap();
+    let mut s = 0;
+    let mut e = 1;
 
-    let s = 0;
-    let mut e = 0;
-
-    for next_digit in iter {
-        if first_digit == *next_digit {
-            e += 1
+    while let Some(first_digit) = input.get(s) {
+        while let Some(next_digit) = input.get(e) {
+            if first_digit == next_digit {
+                e += 1;
             } else {
                 break;
             }
         }
 
-    let mut result = look_and_say(&input[s..=e]);
+        result.append(&mut look_and_say(&input[s..e]));
 
-    result.append(&mut recurse(input[e + 1..].to_vec()));
+        s = e;
+
+        if e == input.len() {
+            break;
+        }
+    }
 
     result
 }
@@ -64,7 +60,7 @@ fn look_and_say(s: &[char]) -> Vec<char> {
 
 #[cfg(test)]
 mod test {
-    use crate::{look_and_say, recurse};
+    use crate::look_and_say;
 
     #[test]
     fn basic() {
@@ -80,17 +76,6 @@ mod test {
         let result = look_and_say(&x);
         assert_eq!(result, vec!['1', '2']);
     }
-
-    #[test]
-    fn test_recurse() {
-        // let x = vec!['1'];
-        // let result = recurse(x);
-        // assert_eq!(result, vec!['1', '1']);
-
-        let result = vec!['1', '1', '1', '2', '2', '1'];
-        let result = recurse(result);
-        assert_eq!(result, vec!['3', '1', '2', '2', '1', '1']);
-    }
 }
 
 // https://adventofcode.com/2015/day/10