Tidy up day 7 a little

diff --git a/src/day07.rs b/src/day07.rs
index 63cd0d4be954c5ed99b7020a0a797a9f7f13bd2a..d8e3d9d5a78ccbe002217dd9e223638fa93484b6 100644 (file)
--- a/src/day07.rs
+++ b/src/day07.rs
@@ -4,7 +4,7 @@ fn input() -> &'static str {
 
 fn parse(input: &str) -> Vec<(u64, Vec<u64>)> {
     input
-        .split_terminator("\n")
+        .lines()
         .map(|l| {
             let [lhs, rhs] = l.split(":").collect::<Vec<_>>()[..] else {
                 panic!()
@@ -88,7 +88,7 @@ fn op_eval(num: &[u64], op: &[Op]) -> u64 {
         .fold(num[0], |a, (b, x)| match x {
             Op::Add => a + b,
             Op::Mul => a * b,
-            Op::Cat => a * 10u64.pow(b.ilog10() + 1) + b,
+            Op::Cat => a * b.next_multiple_of(10) + b,
         })
 }
 
@@ -134,26 +134,34 @@ mod test {
         "292: 11 6 16 20\n",
     );
 
+    #[rustfmt::skip]
     #[test]
     fn test_parse() {
         assert_eq!(
             parse(INPUT_STR),
             [
-                (190, vec![10, 19]),
-                (3267, vec![81, 40, 27]),
-                (83, vec![17, 5]),
-                (156, vec![15, 6]),
-                (7290, vec![6, 8, 6, 15]),
+                (190,    vec![10, 19]),
+                (3267,   vec![81, 40, 27]),
+                (83,     vec![17, 5]),
+                (156,    vec![15, 6]),
+                (7290,   vec![6,  8,  6,  15]),
                 (161011, vec![16, 10, 13]),
-                (192, vec![17, 8, 14]),
-                (21037, vec![9, 7, 18, 13]),
-                (292, vec![11, 6, 16, 20])
+                (192,    vec![17, 8,  14]),
+                (21037,  vec![9,  7,  18, 13]),
+                (292,    vec![11, 6,  16, 20])
             ]
         )
     }
 
     #[test]
-    fn test_op_eval() {
+    fn test_op_eval_ops() {
+        assert_eq!(op_eval(&[1, 1], &[Op::Add]), 2);
+        assert_eq!(op_eval(&[1, 1], &[Op::Mul]), 1);
+        assert_eq!(op_eval(&[1, 1], &[Op::Cat]), 11);
+    }
+
+    #[test]
+    fn test_op_eval_fold() {
         assert_eq!(op_eval(&[1, 2, 3], &[Op::Add, Op::Mul]), 9)
     }
 
@@ -166,32 +174,20 @@ mod test {
         )
     }
 
+    #[rustfmt::skip]
     #[test]
     fn test_opstring_with_cat() {
         use Op::*;
         assert_eq!(
             OpString::new_with_cat(2).collect::<Vec<_>>(),
             [
-                [Add, Add],
-                [Add, Mul],
-                [Add, Cat],
-                [Mul, Add],
-                [Mul, Mul],
-                [Mul, Cat],
-                [Cat, Add],
-                [Cat, Mul],
-                [Cat, Cat],
+                [Add, Add], [Add, Mul], [Add, Cat],
+                [Mul, Add], [Mul, Mul], [Mul, Cat],
+                [Cat, Add], [Cat, Mul], [Cat, Cat],
             ]
         )
     }
 
-    #[test]
-    fn test_check_op_eval() {
-        assert_eq!(op_eval(&[1, 1], &[Op::Add]), 2);
-        assert_eq!(op_eval(&[1, 1], &[Op::Mul]), 1);
-        assert_eq!(op_eval(&[1, 1], &[Op::Cat]), 11);
-    }
-
     #[test]
     fn test_check_ops() {
         assert_eq!(