use std::fs;
use std::char;

fn main() {
    let lines = fs::read_to_string("input").expect("Unable to read file");

    //Part 1
    println!("{}", reduce(lines.clone()));

    //Part 2

    let mut all_lengths: Vec<i32> = Vec::new();

    for i in 0..26 {
        let big_char = char::from_u32(65+i).unwrap();
        let little_char = char::from_u32(97+i).unwrap();

        let string = lines.clone().replace(big_char, "").replace(little_char, "");

        all_lengths.push(reduce(string));
    }

    println!("{}", all_lengths.iter().min().unwrap());
}

fn reduce(string: String) -> i32 {
    let mut current_string = string;
    let mut new_string: Vec<char>;
    let mut last_string = String::new();

    while last_string != current_string {
        let all_chars: Vec<char> = current_string.chars().into_iter().collect();
        let mut count = 0;

        new_string = Vec::new();

        while count < all_chars.len() - 1 {
            let cur_char_uppercase = all_chars[count].to_uppercase().collect::<Vec<char>>()[0];
            let cur_char_lowercase = all_chars[count].to_lowercase().collect::<Vec<char>>()[0];

            if all_chars[count] == cur_char_lowercase {
                if all_chars[count + 1] == cur_char_uppercase{
                    count += 1;
                } else {
                    new_string.push(all_chars[count].clone());
                }
            } else {
                if all_chars[count + 1] == cur_char_lowercase{
                    count += 1;
                } else {
                    new_string.push(all_chars[count].clone());
                }
            }

            count += 1;
        }

        new_string.push(all_chars[all_chars.len() - 1].clone());

        last_string= current_string.clone();
        current_string = new_string.clone().into_iter().collect();
    }

    return (current_string.len()-1) as i32
}