solution refactoring: day 1, with BinaryHeap<Reverse<T>>

src/days/d1.rs

@@ -1,47 +1,39 @@
 use crate::prelude::*;
 
-pub type I = (Vec<u32>, Vec<u32>);
+pub type I = (B<Rev<u32>>, B<Rev<u32>>);
 pub type O = u32;
 
 fn _parse (data: &str) -> I {
-    let (mut l, mut r) = (vec![], vec![]);
+    let (mut l, mut r) = (B::new(), B::new());
     data.lines().for_each(|line| {
         let mut iter = line.split_whitespace();
 
         let left = p!(n!(iter));
         let right = p!(n!(iter));
-        l.push(left);
+        l.push(Rev(left));
-        r.push(right);
+        r.push(Rev(right));
     });
 
     (l, r)
 }
 
-fn _silver ((mut left, mut right): I) -> O {
+fn _silver ((left, right): I) -> O {
-    left.sort();
+    left.into_iter_sorted().zip(right.into_iter_sorted()).fold(0, |acc, (l, r)| ({ println!("{:?}", (acc, l, r)); 0 }) + acc + l.0.abs_diff(r.0))
-    right.sort();
-
-    left.into_iter().zip(right.into_iter()).fold(0, |acc, (l, r)| acc + l.abs_diff(r))
 }
 
 fn _gold ((left, right): I) -> O {
-    let right = right.into_iter().counts();
+    let right = right.into_iter().map(|e| e.0).counts();
 
-    left.into_iter().fold(0, |acc, cur| acc + cur * *right.get(&cur).unwrap_or(&0) as u32)
+    left.into_iter().fold(0, |acc, cur| acc + cur.0 * *right.get(&cur.0).unwrap_or(&0) as u32)
 }
 
 #[cfg(test)]
 mod test {
     use super::*;
 
-    fn read () -> I {
-        let data = inc!(1);
-        _parse(data)
-    }
-
     #[test]
     fn silver () {
-        let data = read();
+        let data = _parse(inc!(1));
         let ans = _silver(data);
 
         assert_eq!(ans, 2196996)
@@ -49,7 +41,7 @@ mod test {
 
     #[test]
     fn gold () {
-        let data = read();
+        let data = _parse(inc!(1));
         let ans = _gold(data);
 
         assert_eq!(ans, 23655822)

src/lib.rs

@@ -2,6 +2,7 @@
 #![feature(array_windows)]
 #![feature(decl_macro)]
 #![feature(iter_array_chunks)]
+#![feature(binary_heap_into_iter_sorted)]
 
 pub mod days;
 pub mod utils;

src/prelude.rs

@@ -8,7 +8,10 @@ pub use std::{
         VecDeque as D,
         BinaryHeap as B,
     },
-    cmp::Ordering as Or,
+    cmp::{
+        Ordering as Or,
+        Reverse as Rev,
+    },
 };
 
 pub type SS = &'static str;