From b5da2fa328ad63d683d66da65e656ed2ee64878c Mon Sep 17 00:00:00 2001 From: Curtis McEnroe Date: Mon, 27 Nov 2017 17:11:18 -0500 Subject: Move to 2016 directory --- 2016/src/bin/day19.rs | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 2016/src/bin/day19.rs (limited to '2016/src/bin/day19.rs') diff --git a/2016/src/bin/day19.rs b/2016/src/bin/day19.rs new file mode 100644 index 0000000..9afbf39 --- /dev/null +++ b/2016/src/bin/day19.rs @@ -0,0 +1,35 @@ +use std::collections::VecDeque; +use std::io::{self, Read}; + +#[derive(Clone, Copy)] +struct Elf { + position: usize, + gifts: usize, +} + +fn solve(count: usize) -> usize { + let mut circle: VecDeque = (0..count) + .map(|i| Elf { position: i + 1, gifts: 1 }) + .collect(); + + while circle.len() > 1 { + let mut current = circle.pop_front().unwrap(); + let next = circle.pop_front().unwrap(); + current.gifts += next.gifts; + circle.push_back(current); + } + + circle.pop_front().unwrap().position +} + +fn main() { + let mut input = String::new(); + io::stdin().read_to_string(&mut input).unwrap(); + + println!("Part 1: {}", solve(input.trim().parse().unwrap())); +} + +#[test] +fn part1() { + assert_eq!(3, solve(5)); +} -- cgit 1.4.1