solution: day12

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}