reduced overhead by passing an owned string

src/day01/mod.rs

@@ -18,11 +18,11 @@ L82";
 
     #[test]
     fn part01a() {
-        assert_eq!(part01a::solve(PUZZLE.to_string()), 3);
+        assert_eq!(part01a::solve(PUZZLE), 3);
     }
 
     #[test]
     fn part01b() {
-        assert_eq!(part01b::solve(PUZZLE.to_string()), 6);
+        assert_eq!(part01b::solve(PUZZLE), 6);
     }
 }