day 3: part 1: rust

2024/days/03/part1/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "part1"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+regex = "1.11.1"

2024/days/03/part1/src/main.rs

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+use regex::Regex;
+
+fn main() -> std::io::Result<()> {
+    let mut sum: u32 = 0;
+    let re = Regex::new(r"mul\(([0-9]*),([0-9]*)\)").unwrap();
+    let hay = std::io::read_to_string(std::io::stdin()).unwrap();
+    for (_, [num1, num2]) in re.captures_iter(&hay).map(|c| c.extract()) {
+        let num1: u32 = num1.parse().unwrap();
+        let num2: u32 = num2.parse().unwrap();
+        sum += num1 * num2;
+    }
+    println!("{}", sum);
+    Ok(())
+}