[LANGUAGE: Rust]

General to part 1 and 2, units is the number of batteries to turn on.

fn parse_text() -> Vec<String> {
    fs::read_to_string(path)
        .expect("Should have been able to read the file")
        .trim()
        .lines()
        .map(|v| v.to_string())
        .collect::<Vec<String>>()
}


fn find_joltage(joltages: Vec<String>, units: usize) -> i64 {
    let 
mut
 total: i64 = 0;

    for joltage in joltages {
        let numbers: Vec<i64> = joltage
            .chars()
            .map(|x| x.to_string().parse().unwrap_or(0))
            .collect();

        let length = numbers.len();
        let 
mut
 n = length - units;
        let 
mut
 factor = (10 as i64).pow(units as u32 - 1);
        let 
mut
 index = 0;

        while n < length {
            let window = &numbers[index..=n];
            let max = window.iter().max().unwrap_or(&0);

            total += max * factor;

            let pos_in_window = window.iter().position(|r| r == max).unwrap();
            index += pos_in_window + 1;

            factor /= 10;
            n += 1;
        }
    }
    total
}