use std::{
    collections::{HashMap, HashSet},
    mem::swap,
};

fn main() {
    let input = include_str!("../../input.txt").trim();

    let input: Vec<&str> = input.trim().split("\n").collect();
    // let width = input[0].len() as u64;
    let start = input[0].find("S").unwrap() as u64;
    let splitters_map: Vec<HashSet<u64>> = input[0..input.len()]
        .iter()
        .enumerate()
        .map(|(i, line)| if i % 2 != 0 { "" } else { line })
        .filter(|line| line != &"")
        .map(|line| {
            line.chars()
                .enumerate()
                .fold(HashSet::new(), |mut s, (i, char)| {
                    if char == '^' {
                        s.insert(i as u64);
                    }
                    s
                })
        })
        .collect();

    let timelines = {
        let mut timelines: HashMap<u64, u64> = HashMap::new();
        timelines.insert(start, 1);
        let mut timelines_new: HashMap<u64, u64> = HashMap::new();
        for splitters in splitters_map {
            for (pos, amount) in &timelines {
                if splitters.contains(&pos) {
                    let m1 = timelines_new.entry(pos - 1).or_insert(0);
                    *m1 += amount;
                    let p1 = timelines_new.entry(pos + 1).or_insert(0);
                    *p1 += amount;
                } else {
                    let e = timelines_new.entry(*pos).or_insert(0);
                    *e += amount;
                }
            }
            // for pos in 0..width as u64 {
            //     if splitters.contains(&pos) {
            //         print!("^");
            //     } else if timelines_new.contains_key(&pos) {
            //         print!("|");
            //     } else {
            //         print!(".");
            //     }
            // }
            // print!("\n\n");
            swap(&mut timelines, &mut timelines_new);
            timelines_new.clear();
        }
        timelines
    };
    // println!("{:?}", timelines);
    println!("{}", timelines.iter().fold(0, |acc, v| { acc + v.1 }))
}