2022, day3: done

1 files changed, 31 insertions, 0 deletions

diff --git a/2022/day3/part2/src/main.rs b/2022/day3/part2/src/main.rs
new file mode 100644
index 0000000..7139eb0
--- /dev/null
+++ b/2022/day3/part2/src/main.rs
@@ -0,0 +1,31 @@
+use itertools::Itertools;
+use std::collections::HashMap;
+use std::collections::HashSet;
+
+fn main() {
+    let mut sum = 0;
+    for group in &include_str!("../../input").lines().chunks(3) {
+        let mut membership: HashMap<char, usize> = HashMap::new();
+        for rucksack in group {
+            let mut items: HashSet<char> = HashSet::new();
+            for item in &rucksack.chars().chunks(2) {
+                for c in item {
+                    items.insert(c);
+                }
+            }
+            for c in &items {
+                *membership.entry(c.to_owned()).or_default() += 1;
+            }
+        }
+        for (item, value) in membership {
+            if value == 3 {
+                if item.is_lowercase() {
+                    sum += item as i16 - 96;
+                } else {
+                    sum += item as i16 - 38;
+                }
+            }
+        }
+    }
+    println!("{}", sum);
+}