d3p1 optimized

day3/src/main.rs

@@ -8,21 +8,17 @@ fn main() {
     let mut sum: u64 = 0;
     for line in input.lines() {
         let mut left_chars: HashSet<char> = HashSet::new();
-        let mut dupe_chars: HashSet<char> = HashSet::new();
 
         for (i, c) in line.char_indices() {
             if i < line.len()/2 {
                 left_chars.insert(c);
             } else if left_chars.contains(&c) {
-                dupe_chars.insert(c);
-            }
-        }
-
-        for c in dupe_chars {
-            if c >= 'a' && c <= 'z' {
-                sum += (c as u64) - ('a' as u64) + 1;
-            } else {
-                sum += (c as u64) - ('A' as u64) + 27;
+                if c >= 'a' && c <= 'z' {
+                    sum += (c as u64) - ('a' as u64) + 1;
+                } else {
+                    sum += (c as u64) - ('A' as u64) + 27;
+                }
+                break;
             }
         }
     }