Finished first year day 2 aoc

advent_of_code/2015/2/src/main.rs

@@ -0,0 +1,61 @@
+use nom::{
+    bytes::complete::tag,
+    character::complete::{self, newline},
+    combinator::map,
+    multi::separated_list1,
+    sequence::separated_pair,
+    IResult,
+};
+
+fn parse_input(input: &str) -> IResult<&str, Vec<(u64, u64, u64)>> {
+    let (input, dimensions) = separated_list1(
+        newline,
+        map(
+            separated_pair(
+                complete::u64,
+                tag("x"),
+                separated_pair(complete::u64, tag("x"), complete::u64),
+            ),
+            |(x, (y, z))| (x, y, z),
+        ),
+    )(input)?;
+    Ok((input, dimensions))
+}
+
+fn solve_first(dimensions: &[(u64, u64, u64)]) -> u64 {
+    dimensions
+        .iter()
+        .map(|&(l, w, h)| {
+            2 * l * w + 2 * w * h + 2 * l * h + std::cmp::min(l * w, std::cmp::min(w * h, h * l))
+        })
+        .sum()
+}
+
+fn solve_second(dimensions: &[(u64, u64, u64)]) -> u64 {
+    dimensions
+        .iter()
+        .map(|&(l, w, h)| smallest_perimeter(l, w, h) + l * w * h)
+        .sum()
+}
+
+fn smallest_perimeter(l: u64, w: u64, h: u64) -> u64 {
+    (l + w + h - std::cmp::max(l, std::cmp::max(w, h))) * 2
+}
+
+fn main() {
+    println!("Hello, this is Patrick!");
+
+    let input_txt = include_str!("../input.txt");
+    let (_rest, dimensions) = parse_input(input_txt).unwrap_or(("", vec![]));
+
+    let first_result = solve_first(&dimensions[..]);
+
+    println!(
+        "The elves will need {} square feet of wrapping paper",
+        first_result
+    );
+
+    let second_result = solve_second(&dimensions[..]);
+
+    println!("The elves will need {} feet of ribbon", second_result);
+}