solution: day12

Cargo.lock

@@ -30,6 +30,7 @@ dependencies = [
  "hashbrown 0.13.1",
  "hex-literal",
  "itertools",
+ "json",
  "lazy_static",
  "pico-args",
  "regex",
@@ -394,6 +395,12 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "json"
+version = "0.12.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "078e285eafdfb6c4b434e0d31e8cfcb5115b651496faca5749b88fafd4f23bfd"
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"

Cargo.toml

@@ -12,6 +12,7 @@ dotenv = "0.15.0"
 hashbrown = "0.13.1"
 hex-literal = "0.3.4"
 itertools = "0.10.5"
+json = "0.12.4"
 lazy_static = "1.4.0"
 pico-args = "0.5.0"
 regex = "1.7.0"

src/bin/12.rs

@@ -0,0 +1,47 @@
+use json::{parse, JsonValue::*, JsonValue};
+
+fn parse_add(json_object: &JsonValue, skip_red: bool) -> i32 {
+    match json_object {
+        Number(x) => x.to_string().parse::<i32>().unwrap_or(0),
+        Object(x) => {
+            if skip_red {
+                for (_, node) in x.iter() {
+                    if let Short { .. } = node {
+                        if node.as_str() == Some("red") {
+                            return 0;
+                        }
+                    }
+                }
+            }
+            x.iter().map(|(_, x)| parse_add(x, skip_red)).sum()
+        }
+        Array(x) => x.iter().map(|y| parse_add(y, skip_red)).sum(),
+        _ => 0,
+    }
+}
+
+pub fn part_one(input: &str) -> Option<u32> {
+    Some(parse_add(&parse(input).unwrap(), false) as u32)
+}
+pub fn part_two(input: &str) -> Option<u32> {
+    Some(parse_add(&parse(input).unwrap(), true) as u32)
+}
+fn main() {
+    let input = &aoc::read_file("inputs", 12);
+    aoc::solve!(1, part_one, input);
+    aoc::solve!(2, part_two, input);
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn test_part_one() {
+        let input = aoc::read_file("test_inputs", 12);
+        assert_eq!(part_one(&input.trim()), Some(15));
+    }
+    #[test]
+    fn test_part_two() {
+        let input = aoc::read_file("test_inputs", 12);
+        assert_eq!(part_two(&input.trim()), Some(0));
+    }
+}

src/test_inputs/12.txt

@@ -0,0 +1 @@
+{"d":"red","e":[1,2,3,4],"f":5}