day 2

Cargo.lock

@@ -2,6 +2,41 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "aho-corasick"
+version = "0.7.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cc936419f96fa211c1b9166887b38e5e40b19958e5b895be7c1f93adec7071ac"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "aoc2022"
 version = "0.1.0"
+dependencies = [
+ "regex",
+]
+
+[[package]]
+name = "memchr"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
+
+[[package]]
+name = "regex"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e076559ef8e241f2ae3479e36f97bd5741c0330689e217ad51ce2c76808b868a"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.6.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "456c603be3e8d448b072f410900c09faf164fbce2d480456f50eea6e25f9c848"

Cargo.toml

@@ -6,3 +6,5 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+regex = "1.7"
+

examples/day02_1.rs

@@ -0,0 +1,29 @@
+fn score(a: char, b: char) -> i32 {
+    match (a, b) {
+        ('A', 'X') => 1 + 3,
+        ('A', 'Y') => 2 + 6,
+        ('A', 'Z') => 3 + 0,
+        ('B', 'X') => 1 + 0,
+        ('B', 'Y') => 2 + 3,
+        ('B', 'Z') => 3 + 6,
+        ('C', 'X') => 1 + 6,
+        ('C', 'Y') => 2 + 0,
+        ('C', 'Z') => 3 + 3,
+        _ => todo!()
+    }
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let lines: Vec<String> = std::io::stdin().lines().map(|x| x.unwrap()).collect();
+    let mut total = 0;
+    for line in lines {
+        if line.is_empty() { continue; }
+        let mut chars = line.chars();
+        let a = chars.next().unwrap();
+        chars.next();
+        let b = chars.next().unwrap();
+        total += score(a, b);
+    }
+    println!("{}", total);
+    Ok(())
+}

examples/day02_2.rs

@@ -0,0 +1,29 @@
+fn score(a: char, b: char) -> i32 {
+    match (a, b) {
+        ('A', 'X') => 3 + 0,
+        ('A', 'Y') => 1 + 3,
+        ('A', 'Z') => 2 + 6,
+        ('B', 'X') => 1 + 0,
+        ('B', 'Y') => 2 + 3,
+        ('B', 'Z') => 3 + 6,
+        ('C', 'X') => 2 + 0,
+        ('C', 'Y') => 3 + 3,
+        ('C', 'Z') => 1 + 6,
+        _ => todo!()
+    }
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let lines: Vec<String> = std::io::stdin().lines().map(|x| x.unwrap()).collect();
+    let mut total = 0;
+    for line in lines {
+        if line.is_empty() { continue; }
+        let mut chars = line.chars();
+        let a = chars.next().unwrap();
+        chars.next();
+        let b = chars.next().unwrap();
+        total += score(a, b);
+    }
+    println!("{}", total);
+    Ok(())
+}