readying 2022 to merge

2022/day3/src/main.rs

@@ -0,0 +1,90 @@
+#![warn(clippy::all, clippy::pedantic)]
+
+use std::fs;
+
+fn part1(input: &str) -> String {
+    input
+        .lines()
+        .map(|line| {
+            let (comp1, comp2) = line.split_at(line.len() / 2);
+            let duplicate = comp2.chars().find(|c| comp1.contains(*c)).unwrap();
+            match duplicate {
+                n @ 'a'..='z' => (n as i32) - ('a' as i32) + 1_i32,
+                n @ 'A'..='Z' => (n as i32) - ('A' as i32) + 27_i32,
+                _ => 0,
+            }
+        })
+        .sum::<i32>()
+        .to_string()
+}
+
+fn part2(input: &str) -> String {
+    input
+        .lines()
+        .fold(Vec::new(), |mut acc: Vec<Vec<String>>, line| {
+            if acc.is_empty() || acc.last().unwrap().len() == 3 {
+                acc.push(Vec::new());
+            }
+            acc.last_mut().unwrap().push(line.to_owned());
+            acc
+        })
+        .iter()
+        .map(|group| {
+            let [g1, g2, g3] = group.as_slice() else {
+                panic!("not get here")
+            };
+            match g1
+                .chars()
+                .fold(Vec::new(), |mut combo: Vec<char>, ch| {
+                    if g2.contains(ch) {
+                        combo.push(ch);
+                    }
+                    combo
+                })
+                .iter()
+                .find(|c| g3.contains(**c))
+                .unwrap()
+            {
+                n @ 'a'..='z' => (*n as i32) - ('a' as i32) + 1_i32,
+                n @ 'A'..='Z' => (*n as i32) - ('A' as i32) + 27_i32,
+                _ => 0,
+            }
+        })
+        .sum::<i32>()
+        .to_string()
+}
+
+fn main() -> std::io::Result<()> {
+    //Read in file
+    let file = fs::read_to_string("input")?;
+
+    // fold the lines into groups of three
+    println!("Part 1: {}", part1(&file));
+    println!("Part 2: {}", part2(&file));
+    // find common letter in the groups
+    //   find common letters in the first 2 then find the common in the third
+    // sum the common letters
+    Ok(())
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    const INPUT: &str = "vJrwpWtwJgWrhcsFMMfFFhFp
+jqHRNqRjqzjGDLGLrsFMfFZSrLrFZsSL
+PmmdzqPrVvPwwTWBwg
+wMqvLMZHhHMvwLHjbvcjnnSBnvTQFn
+ttgJtRGJQctTZtZT
+CrZsJsPPZsGzwwsLwLmpwMDw";
+
+    #[test]
+    fn part1_works() {
+        assert_eq!(part1(&INPUT), "157");
+    }
+
+    #[test]
+    fn part2_works() {
+        assert_eq!(part2(&INPUT), "70");
+    }
+}