Linter cleanups

src/bin/day14.rs

@@ -74,7 +74,7 @@ fn main() -> Result<(), Box<dyn Error>> {
     let file = File::open("inputs/day14.txt")?;
     let mut lines = io::BufReader::new(file).lines();
 
-    let mut polymer_template: Vec<char> = lines.next().unwrap().unwrap().chars().collect();
+    let polymer_template: Vec<char> = lines.next().unwrap().unwrap().chars().collect();
     lines.next();
 
     let mut rules: HashMap<(char, char), char> = HashMap::new();

src/bin/day16.rs

@@ -1,7 +1,3 @@
-use std::cmp::Ordering;
-use std::collections::BinaryHeap;
-use std::collections::HashMap;
-use std::collections::HashSet;
 use std::error::Error;
 use std::fs::File;
 use std::io::{self, BufRead};

src/bin/day17.rs

@@ -1,11 +1,6 @@
-use std::cmp::Ordering;
-use std::collections::BinaryHeap;
-use std::collections::HashMap;
-use std::collections::HashSet;
 use std::error::Error;
 use std::fs::File;
 use std::io::{self, BufRead};
-use std::vec::Vec;
 
 #[macro_use]
 extern crate lazy_static;
@@ -35,7 +30,11 @@ fn is_hit(
         }
 
         if vx != 0 {
-            vx -= 1;
+            if vx > 0 {
+                vx -= 1;
+            } else {
+                vx += 1;
+            }
         }
         vy -= 1;
 
@@ -90,7 +89,7 @@ fn main() -> Result<(), Box<dyn Error>> {
 
     let mut hits = 0;
 
-    for vx in -256..256 {
+    for vx in 0..256 {
         for vy in -256..246 {
             let (hit, local_max_y) = is_hit(vx, vy, target.0, target.1, target.2, target.3);
             if hit {